They might be really intrigued. Some like Midoriya would be taking notes on the unique storylines and character developments in the fanfiction, comparing them to his own experiences with quirks and heroism.
The teachers in BNHA, like Aizawa, would be analyzing the fanfiction from a more educational perspective. He might use it as an example in class to talk about different ways of portraying heroes, and how the Avengers' world differs from their own in terms of powers and teamwork.
They might be quite surprised. Some characters could be flattered by the creative interpretations in the fanfiction. For example, Alexander Hamilton himself might be amazed at how fans have imagined different scenarios for his life and relationships.
They might be surprised at how their actions are reimagined. For example, Iron Man could be astounded to see a version of himself in a situation he never thought of in the official storylines.
They might be amused. They could find some fanfictions that depict them in ways they never thought of, which might make them chuckle at the creativity of the fans.
Well, Hulk might not care much at all. He's more into his own world most of the time. Black Widow herself, if she were alive to see it, might be flattered or a bit embarrassed depending on how the fanfiction depicted her. Hawkeye would likely just roll his eyes and say something like 'People have too much time on their hands'. But overall, it would be a really odd situation for the Avengers to be in, watching something that's created by fans rather than the official Marvel universe.
Ruby would be the first to jump into reading or listening to the Avengers fanfiction. She'd be all wide - eyed and eager, enjoying every bit of it. Weiss would probably roll her eyes at first but then get drawn in, especially if there was some complex plot or character development. Blake would be quiet as she absorbed it all, thinking about how it compares to the books she's read. Yang would be like, 'This is so cool!' or 'This is just plain bad' depending on what she was reading. They all would bring their own unique perspectives from their own experiences in Remnant to their view of the Avengers fanfiction.
They might be really surprised. Some fanfictions could have unique interpretations of their characters. For example, they might be amused by the creative storylines that give their characters new powers or relationships. It could also make them think about how the fans see them.
The Avengers might have a range of reactions. Tony Stark could be making sarcastic comments throughout, perhaps critiquing the plot holes in the fanfiction. Captain America might be a bit confused at first, not fully understanding the concept of fan - made stories, but then getting into the spirit of it. Thor would probably find the whole thing quite amusing and laugh heartily at the more outlandish parts.
They might be really surprised. The Avengers are used to their own set of adventures, and this fanfiction about 'The Impossible' would show them in a whole new scenario that they may not have expected. It could be both exciting and a bit strange for them to see this new take on their characters.
They might be really surprised. For example, if Optimus Prime from the Transformers universe were to watch Bumblebee fanfiction, he'd probably be taken aback by some of the creative interpretations of Bumblebee's adventures that fans come up with. It could also make him reflect on his relationship with Bumblebee in a new light.
Well, it depends on the characters. Some might be amused, like Joseph Joestar. He might find the wild and creative interpretations in the fanfiction quite entertaining and laugh out loud at some of the over - the - top scenarios. Others, like Jotaro Kujo, might be a bit more critical. He'd probably analyze it closely, maybe even scoff at inaccuracies or out - of - character portrayals. And then there are those like Dio who would either be enraged if the fanfiction didn't show him in a 'glorious' enough light or be secretly pleased if it painted him as an even greater villain.