They might be very excited. They could cheer loudly for Harry, showing their support and pride in him as a friend.
Well, perhaps some of the Weasleys, like Ron, would be on the edge of their seats, feeling a bit nervous for Harry. They know how dangerous dueling can be, even in a fictional setting. And Ginny might be looking at Harry with admiration, seeing his skills and courage in the duel. Fred and George might be making jokes about the whole situation, but still be fully engaged in watching Harry.
For the Weasleys, they could be excited to meet Hermione's parents. Arthur Weasley might be especially interested in learning about muggle things from the Grangers. The Grangers may be a bit overwhelmed by the Weasleys' boisterous nature and the presence of magic, but they would also be glad to see the family their daughter is so close to. They might start to relax as they see how kind and inclusive the Weasleys are.
It could boost his confidence. Knowing that the Weasleys are there watching him, Harry might feel more determined to do well.
If the Weasleys watch Harry's memories in fanfiction, it could change their relationships. Molly Weasley, for instance, might become more motherly towards Harry than she already is. The younger Weasleys could look at Harry in a whole new light, seeing him not just as their friend but as someone who has overcome great hardships. And Mr. Weasley might use the knowledge from Harry's memories to better understand the wizarding world's darker side that has affected Harry so much.
Well, one possible plot could be that Harry would finally experience a warm family life. He'd grow up with the Weasleys' chaos and love. He might learn more about magic in a different way than at Hogwarts, with Molly Weasley's home - cooked meals and Arthur's fascination with Muggle objects influencing him. The Weasley siblings would become his true brothers and sisters, and they'd all get into various adventures together around the Burrow.
They would probably be very emotional. Some of them might cry, especially Molly, seeing all the pain Harry has been through.
They might be amused. After all, it's interesting to see different interpretations of their own family story.
Some of them might be critical. Captain America, being a traditionalist, could have issues with how the fanfiction might deviate from the 'true' version of Iron Man he knows. He might think some characterizations are inaccurate. Hulk, on the other hand, might not care much at first, but if the fanfiction angers him in some way, like making Iron Man look bad when he shouldn't, he could get a bit riled up.
Well, Ruby would likely find it super cool. She loves new things and new characters. Weiss would probably look for proper grammar and a well - structured plot. If the OC has some kind of noble background or is related to Atlas in the fanfiction, she'd be more interested. Blake would be into the deeper themes and the relationships the OC has. Yang would enjoy seeing the OC show off some badass fighting moves. Overall, their reactions would vary based on their own personalities and what aspects of the RWBY world the fanfiction touches on.
Well, Ruby would likely love it immediately. She has a big heart for all things fun and different, and chibi fanfiction often has that charm. Weiss might take a moment to adjust, but once she realizes it's all in good fun, she'd enjoy it too. Blake, being a fan of stories herself, would be interested in seeing how others portray the RWBY world in this unique chibi style. Yang would be the most vocal, sharing her favorite parts with the others and maybe even getting some ideas for pranks from the wacky scenarios in the fanfiction.
Some characters might be shocked. For example, Ichigo might be surprised by the future battles and the development of his friends. He could see new powers emerging and might start to train harder in the present to face the future challenges.