Well, some relationships might become stronger. For example, Thor and Rocket might bond more over their shared experiences in Endgame. They could start to rely on each other even more in future battles.
After watching Endgame, the relationship between Tony Stark's family (Pepper and Morgan) and the other Avengers could change significantly. The Avengers might be more protective of them, seeing how much Tony gave up. Also, Morgan could start to look up to the other Avengers like her father, and they in turn could become sort of surrogate uncles and aunts to her, which would add a whole new family - dynamic aspect to the fanfiction.
In some fanfictions, Steve Rogers and Natasha Romanoff's relationship could take an interesting turn. Maybe after watching Endgame and seeing how much they sacrificed, they start to see each other in a different light, not just as comrades but as something more. They might start to have deeper conversations about their pasts and futures.
The Avengers might start to see Iron Man in a new light. The fanfiction could highlight aspects of his character that they hadn't really considered before. This could lead to a deeper understanding and respect among them for Iron Man and also for each other as they discuss these new perspectives.
Some characters might start to question their own actions. For example, if they read a fanfiction that presents a different moral view of their decisions in Endgame, it could make them rethink what they did. Hulk might read a fanfiction where his decision to merge with Banner is presented in a negative light, and it could make him wonder if he made the right choice.
They could become closer. Sharing a laugh over some of the wilder fanfiction plots would create a new bond. For example, if there was a really out - there story about Hawkeye and Black Widow having secret superpowers, they could joke about it together.
Some relationships might become stronger. If they read fanfiction that shows deep friendships between them, they could be more aware of their bond. For example, if there are stories about Iron Man and Captain America's friendship overcoming differences, they might be more likely to work together better.
Conversely, relationships could also be strained. If the fanfiction portrays a character in a way that another character doesn't like, such as making one character overly jealous or possessive of another in a way that goes against their normal dynamic, it could cause tension between them. For instance, if a fanfiction makes a brother - sister relationship seem romantic in a wrong way, it would create problems.
Well, in some fanfictions, Tony and Steve's relationship could be completely different during the reverse time heist. Maybe they start to understand each other better as they work together in the past. They could see the reasons behind each other's actions in a new light.
If Peter was adopted by the Avengers, his relationship with Wanda Maximoff could be quite special. Wanda could help Peter understand and control his emotions better, especially when he's under stress during battles. Peter could also befriend Vision, and together they could explore the boundaries of science and magic. The Avengers would start to see Peter as a full - fledged member of the family. They would be more protective of him, and Peter would feel a stronger sense of belonging. His relationships would no longer be just about superhero partnerships but would be about real family connections. For example, they would celebrate holidays together and have family - style dinners, which would strengthen their bonds even more.
Some relationships might be tested. If the fanfiction portrays one Avenger in a bad light or has a conflict between two of them that's different from what they know, there could be some tension. But they'd also realize it's just a fan's interpretation. Hawkeye might be a bit miffed if the fanfiction makes him seem less important, for instance.
If Tony didn't die, the story would be drastically different. For one, the Avengers would still have his leadership and resources. His presence would change the dynamic during the post - Endgame events. They wouldn't be mourning his loss, but instead, be planning new strategies with him at the helm.
The living situation could also create some new tensions. Clint might get annoyed with Thor's loud and boisterous behavior. But at the same time, they could also learn to understand and respect each other better. Maybe Clint would start to appreciate Thor's warrior spirit, and Thor would see Clint's skills in a new light. Natasha, being the observant one, would probably play a role in smoothing out any rough patches in the relationships among the team members.