From 4chan. Likely April Fools Day BS but fun nonetheless:
-From a screening. Effects were unfinished and editing seemed in progress. Placeholder score.
-Opening scene is a silent montage of remaining Avengers + Nebula and Rocket immediately following the snap. The Avengers regroup on the battlefield. Steve looks more angry than sad now. Tony and Nebula board Benatar in silence. Hawkeye's family disappearing is not in the beginning of the movie.
-Title.
-Tony and Nebula in space. This goes about as expected. They open up to each other and Tony decides to give it one more try to make it back for Pepper. He uses what's left of his nano-tech suit to repair the ship.
-Back at HQ: Marvel arrives. They brief her. Shortly after, they receive a transmission from Tony. Tony and Nebula arrive at Avengers HQ.
-Team meeting. Tony is defeated and doesn't believe they can beat Thanos while he has the gauntlet. He and Cap have a pretty bitter reunion. He leaves to go be with Pepper. The rest of them leave to go find Thanos.
-Somewhere in here Tony returns to Pepper. He tells her that he won't leave again unless he's actually sure they can fix this thing, and she has to be prepared for that possibility.
-They find Thanos on his farm. He looks pretty sick and weak, and he's talking to soul Gamora before the Avengers arrive. They fight and the Avengers seem to have the upper hand. Thanos seems to realize this and tells them they won't be able to reverse the snap because the gauntlet is damaged, but he's willing to give it to them if they spare his life. He can't promise they'll all get out of this alive if they continue to fight. The team decides to take the gauntlet and leave Thanos to die alone on his farm but Nebula pulls a fast one and puts on the gauntlet to kill him. It blows her arm off and Thanos comments on how she couldn't even wield the gauntlet in its weakened state. The others hold Nebula back from Thanos and retreat onto the ship while Marvel captures the gauntlet in a stasis kind of thing with her powers.
-They return the gauntlet to HQ and they don't know what to do next. Bruce says he'll look for a way to repair it but he can't promise anything.
-Time jump happens. 5 years
-Some establishing shots and short scenes showing what everyone has been up to. Can't remember them all, but there's one with Tony and Pepper, and they have a kid. Thor is with the Asgardians. Rocket, Nebula, and Banner are still working on gauntlet but close to giving up. Cap has been using Stark's memory tech to relive old memories of Peggy. He doesn't seem to be doing well.
-Ant Man escapes quantum realm through a time vortex thing and finds his daughter, who explains what happened. He goes to Avengers HQ and they discuss what happened to him. They call Tony and Marvel in and they agree that they may have a chance at fixing things with this new intel. Everyone takes off in separate directions to get the team together and do research.
-Tony, Cap, and Marvel go to Wakanda to retrieve some of Shuri's info on the mind stone.
-Widow goes to get Clint in Japan. The scene starts with Clint reliving the snap. Clint is fighting some weird Asian gangster monsters.
-Rocket goes to get Thor.
-While everyone is gone, Banner has an incident with the quantum realm tech in the lab and merges his mind with the Hulk's. The group returns to Banner in Hulk's body.
-The Avengers meet up and prepare. Tony and Cap have an extended sequence here. They talk about moving on if they're successful, and Cap isn't sure he'll ever be able to move on. Minor time jump here, maybe a couple of weeks or months at the most.
-Tony explains the plan. They believe it's possible to repair/recharge the stones by exposing them to past versions of themselves. Tony, Rocket, Banner, and Nebula (maybe?) use Tony's memory tech to create a device to navigate through time using the quantum realm and memories. The biggest problem though is that they can't affect the future so they need to be careful and blend in when they can. They track the energy signatures of the stones through the quantum realm to find locations to travel to, making the whole thing a bit of a crapshoot. This is why they don't arrive at the most convient locations every time. Each stone needs to be transported and taken back in time (they make some containment thing for them.) Before they suit up, Cap stands up and says Avengers Assemble. He doesn't shout it in the middle of battle or anything like that. They manage to make it not cheesy. The quantum suits are just for travel and have a nano housing unit like Tony had.
-Pepper and Tony say goodbye.
-The activities of each time travel group happen at the same time. Ill try my best to remember how it goes.
-Thor takes the power stone and meets up with the past Guardians when they had the power stone in their possession. He's with Rocket and Nebula. There's a skirmish, but they're ultimately able to repair the stone. They return the power stone to the HQ gauntlet and Thor takes the reality stone to past Asgard to repair it. They fix it without issue. Thor has to leave knowing he won't see his mother again.
-Somewhere in the middle of this, Thanos is still on his farm and soul Gamora is talking to him still, even without the gauntlet. He's gone a little crazy. He feels a disturbance with the stones and soul Gamora explains how he is forever tethered to the stones. He turns out to have a beacon of some sort and calls the Outriders, suspecting the Avengers are up to something. One of their ships show up to his farm.
-Meanwhile: Tony, Cap, Rhodey, and Scott follow a powerful energy signature and end up in the Battle of NYC. Lots of good Cap/Tony moments. Interavtions between present and past Avengers, particularly Thor and Tony. Tony takes the broken mind stone and is able to get it repaired. There's a funny scene where Ant Man shrinks and whispers things into Loki's ear to make him think he's going crazy. Cap takes the space stone and repairs it with Rhodey's help, who wears an Iron Man suit to blend in. Stan Lee cameo here. He's a pedestrian who is saved by the two separate Captain Americas one after another. He checks his glasses.
-Marvel transports the busted time stone with Widow, Banner and Clint.They go to repair it with help from Wong and the Ancient One. She warns them about consequences of time travel. They return the the complex some time after Thor and company returned the repaired power stone, replace the time stone in the gauntlet, and are surprised by an attack on HQ by the Outriders.
-Marvel and Hulk hold back the onslaught and it's left to Widow and Clint to protect the gauntlet from any stragglers.They miraculously hold the army back until more Avengers finish their quantum shenanigans and return. Thanos comes down to join the fight. He gets the gauntlet with the repaired power and time stones in it. He heals himself and the gauntlet with the two repaired stones. He proceeds to absolutely wreck the Avengers in a crazy fight, collecting the reality and mind stone as he fights through them. Tony and Rhodey use new armor. Rhodey is killed sacrificing himself so that the group can escape through a portal created by Cap after he successfully wields the space stone.
-The gang are in hiding at a hidden backup HQ. They're all pretty broken up. They decide to make a final push against Thanos with the space stone, deciding there's no way they could win without it.
-Thanos is super pissed. He goes to NYC with the Outriders and just starts destroying everything to bait out the Avengers in hopes of getting the final stone.
The group recruit some extra help. Wakandans. Asgardians. Pepper insists on coming and Tony gives her armor. They launch an assault on Thanos.
-The fight goes well at first. Cap uses the space stone to launch surprise attacks on Thanos. But, Thanos is able to rebuild the gauntlet after he tricks Cap and steals the stone from him. He's also able to repair the soul stone with the power of the other 5 stones, much to everyone's surprise.
-Things get worse and worse. He's pretty much kicking their asses. Thanos says that once they're all dead he plans to clear out another 50 percent of the population to teach them all a lesson. He bloodthirsty at this point.
- Thanos' hubris gets the better of him and Clint is able to knock the soul stone out of the gauntlet with a surprise attack. Thor wields the soul stone and is teleported to a strange place where he talks with his dead relatives. Gets a pep talk. He comes back and resurrects the fallen heroes with the soul stone. They attack.
-So much happens in this fight and everyone has a moment to shine, but I don't remember all of it. Marvel knocks a stone out of the gauntlet, so does Scarlett Witch and Strange. Once all of the stones are removed and gathered by various Avengers, Hulk and Thanos have their rematch. Hulk holds him down and Nebula is able to remove the gauntlet and hand it off to Marvel as Thanos crushes and kills her.
-Another wave of Outriders hit the city. Hulk and most of the Avengers are tied up. Marvel reassembles the gauntlet with the help of Spider-Man and the Guardians before she is attacked and tossed to the side by Thanos. Cap faces Thanos head on and gets the **** kicked out of him but keeps standing up.
-Tony picks up the gauntlet and wields it. He snaps his fingers and disintegrates along with the gauntlet and the stones. The Outriders all disappear. Thanos also disintegrates.
-Thanos goes into the soul stone again and Gamora says goodbye to him before they both disappear, presumably dead. (Gamora and Vision seem to be permadead since they were linked to stones.) Time has been turned back and the city is no longer in shambles. Tony basically just turned back the clock. Everyone is back where they were right before Thanos' assault on Earth started. Only this time Tony and Thanos are gone. All the Avengers retain the memory of what happened.
-We get a pretty long epilogue. Thor has established a new home with his people and maintains a friendship with Rocket and the Guardians. Cap has joined Fury in a leadership role at the new Shield. He puts his picture of Peggy away in a drawer. Accords have been reversed. Clint is back with his family. They all meet up together with basically every character for a Tony Stark memorial. It's revealed that Pepper was pregnant before the events of Infinity War and had Tony's child. Movie ends with Strange, Marvel, Spider-Man, Panther, Ant-Man and the Wasp at a new Avengers facility overseen by Cap.
-Mid-credit: Cap, Widow, Banner, Thor and Clint are having an Avengers reunion party sometime later. Playing beer pong. There's an empty Iron Man suit seated on the couch.
-Post credits: Dr. Strange arrives in Thor's new home and they explain to him that something strange has happened. He comes face to face with a weird cosmic being in the throne room, who promises him that repercussions for humanity's transgressions are coming.