Some Avengers might be really confused at first. For example, Tony Stark would probably be intrigued yet find it a bit odd. He'd be analyzing it like he does with new tech, trying to understand the appeal and the different universes within the anime fanfiction.
Some characters would likely be entertained. For instance, Loki might enjoy seeing the various ways fans write him as a more complex anti - hero. He'd probably find the creativity in the fanfiction quite appealing.
Well, there are also those characters who might be a bit shocked or confused. Take Levi from Attack on Titan. He's a very serious and no - nonsense type of character. If he were to read some of the fanfic about him that deviated too much from his own self - perception, like being made into a comical or overly emotional character in the fanfic, he might be taken aback at first. But then he might also realize it's just a different interpretation and not take it too seriously.
Tamaki would probably be in awe of the Avengers at first. He might try to imitate their heroic poses and grandeur, thinking it would make him seem more appealing. He could also be a bit intimidated by their power, but would quickly try to befriend them. Haruhi would be more practical. She'd probably be curious about how they got their powers and if there was any scientific explanation behind it all.
Some would be intrigued. Captain America, being an open - minded person, might be interested in seeing different interpretations of their team dynamics. He could even gain new insights about his relationships with his fellow Avengers through the fanfiction.
Thor would likely be the most affected. He has a history with Fenrir as it is from Asgardian mythology. He might be cautious at first, but also feel a sense of kinship. Iron Man would probably be all about analyzing Fenrir, trying to figure out its weaknesses and strengths. Captain America would be on guard, ready to defend his team, but also open to the idea of Fenrir not being an enemy if proven so.
Well, when the Avengers first encounter Sephiroth, they'd be quite surprised. Tony Stark would crack a joke to ease the tension a bit but still be very aware of the danger. Steve Rogers would stand tall and be the first to step forward, showing no fear. Thor would grip his hammer tightly, ready to defend. Bruce Banner would be worried that if Hulk gets involved, it could be a very chaotic battle. The female Avengers like Black Widow and Scarlet Witch would be sizing up Sephiroth, trying to find any chinks in his armor. They'd all be on high alert and start formulating a plan to either defeat or contain this unexpected and very powerful new arrival.
Well, it depends on the nature of the fanfiction. Some anime characters might be amused if the fanfiction is light - hearted and full of comical situations. For example, if it's a fanfic about a cooking competition among the characters from a shonen anime, they might react with good - natured laughter and competitiveness. They could also be confused if the fanfiction takes their story in a very strange or unexpected direction, like suddenly making a character from a historical anime end up in a space adventure.
The characters might also get confused. Fanfictions often have their own unique plotlines that can be quite different from the official story. So when they see these strange twists and turns, like Thanos suddenly becoming good in the fanfiction, they'd be scratching their heads and trying to figure out what's going on.