If the Avengers refuse to fight in a fanfic, the plot could develop in a way that explores the consequences of inaction. Maybe the villains start to take over more territory or cause more harm because there's no one to oppose them directly. This can then lead to a situation where the Avengers have to find alternative ways to stop the villains, like using their intelligence or technology. It might also show how the public reacts to their decision not to fight, which could be either supportive or very critical, adding another layer to the story.
It could create a rift. Some Avengers might still believe in fighting, while others are firmly against it. For instance, Captain America, who has always been about duty and fighting for what's right, might be at odds with Iron Man, who could be more cynical after seeing the consequences of their actions. This would lead to a lot of internal conflict within the group.
One possible reason could be moral conflicts. For example, if the fight involves harming innocent civilians, some Avengers might refuse. Another reason could be internal disagreements within the team. Maybe they don't trust the motives behind the fight or the leadership in that particular fanfic scenario. Also, they could be exhausted from previous battles and simply not in the physical or mental state to engage in another fight.
One possible reason could be that they are disillusioned with the world's political powers. Maybe they see that their previous battles have been exploited by those in power for their own gain, and they no longer want to be pawns. For example, they might have noticed that the destruction they've tried to prevent has been used as an excuse for certain governments to impose harsher control on their people.
The conflict can also drive the story towards a climax. In 'Anna Karenina', the fight between Vronsky and Karenin over Anna leads to Anna's downward spiral. The two men's different approaches to loving her, Vronsky's passionate and somewhat reckless love and Karenin's more traditional and possessive love, ultimately contribute to the tragic end of the story.
Another way the plot could develop is that Harry's rejection of Hogwarts causes a rift in the wizarding world. Some support his decision, seeing it as a brave step towards change, while others condemn him. This leads to a power struggle between different factions. Harry then has to navigate through this complex political situation, trying to prove that his way is better while also facing the challenges of being an outcast from the traditional Hogwarts - centered wizarding society.
The story could develop with Harry using his magic to solve Avengers - related problems. For example, he might use a spell to unlock a locked door in Stark Tower.
It can be quite interesting. The polyamorous aspect adds new layers of complexity and relationship dynamics to the story of the Avengers.
It could develop through shared hardships. With the Civil War tearing the Avengers apart, Pepper and Tony find solace in each other. They become more dependent on one another for emotional support.
Well, the other Avengers might rally around him. They could try to find a way to revive him or figure out what caused his collapse. Maybe Bruce Banner uses his scientific knowledge to run tests on Tony.
When Spiderman joins the Avengers in fanfiction, his character often develops a greater sense of responsibility on a larger scale. He realizes he's part of a bigger team with a global or even universal mission. This makes him more confident in his abilities as he has to step up and face bigger threats alongside more experienced heroes.