Well, it creates drama. Readers like to see their favorite characters in difficult situations. When Percy is wrongly blamed, it makes us feel for him and root for his vindication.
One great 'Percy gets wrongly blamed' fanfiction is 'The False Accusation'. In it, Percy is wrongly blamed for stealing a powerful artifact. The story then unfolds as he tries to clear his name while also dealing with the real culprit who is trying to frame him further.
Well, often in such fanfiction, a theme is the re - evaluation of relationships. When Edward is wrongly blamed, it shakes the relationships he has with other characters like Bella. His friends may also be divided in their loyalty. There could also be a theme of justice, as Edward tries to seek it and clear his name. The fanfiction might explore how the Twilight world's own rules and norms play into this situation of false blame.
Obviously, Edward himself is a central character as he is the one being wrongly blamed. Bella would also be involved as she is closely associated with Edward in the Twilight series. His vampire family, such as Alice, Jasper, Emmett, Rosalie, Carlisle and Esme, would likely be part of the story too. They would either be trying to help him clear his name or be affected by the false blame in some way.
He might try to prove his innocence by gathering evidence. For example, if his sisters wrongly blame him for breaking something, he could look for proof that he wasn't even near the item when it broke.
Eventually, he may reach a point of self - reflection. After some time, Percy might realize that his family's feelings are also important. He could start to reevaluate his actions and his priorities. In some fanfictions, this could lead to him trying to mend the relationship with his family, even if it's a slow and difficult process.
In some Twilight fanfiction, Edward might be blamed because of his over - protective nature. He often makes decisions for Bella without fully considering her own desires, which can be seen as controlling and thus draw blame.
One reason could be for the sake of creating drama. Writers might blame Naruto in fanfiction to stir up conflict and make the story more interesting. For example, they could make him the cause of a rift between other characters.
Well, in a lot of fanfiction, the idea is that Tony's creation of Ultron was a complex situation. He was acting out of fear for the safety of the Earth. The Avengers had faced many threats, and he thought an AI like Ultron could be a preemptive defense. So, the fanfiction authors don't blame him as they understand his motivation and the unforeseen consequences that came with his experiment.
Jealousy could be a reason. Maybe Lincoln got something they wanted, like a new game or a special privilege, and they're trying to get him in trouble out of spite.