How does Steve react when he finds out about Howard in Avengers fanfiction?

They might be shocked and confused. It could lead to a lot of internal conflict and soul-searching among the team.

He might be shocked. Fanfiction can often be quite different from the original source material, and the nogitsune concept is already pretty out - there. So the shock value could be high.

Thor would be quite confused at first. Fanfiction is not something from Asgard. But once he gets the gist, he might say something like 'This is a strange Midgardian custom, but if it shows the great friendship of Steve and Bucky, then it is not all bad.' Meanwhile, Tony would be all over Steve, making snarky comments and asking if he's finally going to admit to some hidden feelings for Bucky according to the fanfiction.

In many fanfictions, Naruto's reaction is a mix of shock and determination. The shock comes from finally learning about his clan, and the determination is to uphold the Uzumaki name. He could start wearing something that represents the Uzumaki clan, like a symbol on his clothing. He also may become more protective of the Uzumaki secrets and legacies he discovers.

Well, Howard Stark might have a range of reactions. He could be in awe of the advancements, or he might feel a bit left behind. Maybe he'd also have some fatherly pride and a desire to have been more involved.

In some fanfictions, Vegeta is initially shocked. He might stand there in silence for a moment, his eyes wide. Then he could feel a strange mix of emotions, like pride and fear. He's proud to be having a child with Bulma but also fears for the safety of his family given his dangerous past and the many enemies he has.

He would be very angry. Naruto is not one to take betrayal lightly.

Steve might compare Tony to Howard based on their personalities or leadership styles. Maybe he points out similarities or contrasts in their decision-making.

Often, Gwaine reacts with acceptance. He's not the type to shun Merlin just because of his magic. Instead, he'll likely embrace it as part of who Merlin is. He could say something like 'Merlin, your magic doesn't change a thing between us. You're still my friend.'

In other cases, Teela's reaction could be a mix of emotions. She could be happy that Adam is such a powerful hero but also a bit sad that he felt the need to keep it a secret from her. This discovery might make her question their entire relationship up to that point, and she may need time to sort out her feelings about it all.