I think Ozpin would have some major changes. In different universes, his role as a mentor or the keeper of secrets could be altered. He might be more open or more secretive. Cinder is also a character that could be very different. Her rise to power or her goals could be completely different in alternate universes. For example, she could be a hero instead of a villain in some versions. This would require a huge shift in her character traits and actions.
Ruby. Since she is the main character, her role and personality can be easily tweaked in alternate universes. For example, she could be more serious or less confident. Blake is also a candidate. Her Faunus heritage could be treated very differently in other universes, which would lead to major changes in her character arc. And then there's Weiss. Her family's influence might be more or less prominent, changing her attitude and actions.
One character that would likely have a different role is Sirius Black. In an alternate universe, he might not have been wrongly imprisoned, and he could be a full - time mentor to Harry. Luna Lovegood could be a more powerful and influential figure in the wizarding world. And Voldemort himself could be a reformed wizard, which would turn the whole story upside down.
Well, Hermione is often depicted in different ways in these fanfics. In some alternate universes, she could be a powerful dark witch instead of the studious and good - hearted character we know. Ron might be a super - confident and arrogant character rather than the sometimes insecure boy in the original story. Also, Snape could be a completely different person. He could be a jolly and friendly teacher rather than the brooding and complex one we are used to.
In this type of fanfiction, the concept of character evolution is fascinating. In an alternate universe, the characters may face different challenges that accelerate or change their growth. For instance, Yang might have to overcome a different kind of personal trauma. Also, the concept of the alternate universe's history and how it affects the RWBY characters is interesting. Maybe there was a different Great War in one universe, and that has shaped the current state of the world and the characters' place in it.
I think all of the main characters in RWBY would have significant role changes in an age - swap fanfic. Ruby's leadership would be more seasoned, Weiss would have more power and influence in Atlas, Blake could be a more established Faunus rights advocate, and Yang would be more composed and a different kind of support for the team. Their relationships with each other would also be different, which would further change their roles in the story as a whole.
He might meet different versions of his friends. For example, a Hermione who is a powerful sorceress ruling a magical kingdom. It would be exciting as he could learn new magic from her and be part of her adventures in this alternate reality.
Perhaps he meets a version of his parents who are still alive. This would be an incredibly emotional encounter for Harry. He would get to know them, and they could teach him things about magic and life that he never had the chance to learn before.
Ruby is often very popular in alternate fanfiction. Her innocent yet determined nature makes her a great character to put in different scenarios. Blake is also popular as her complex backstory and struggle with her identity can be explored in many alternate ways. Yang too, with her strong - willed and fiery personality, often takes center stage in different fan - created stories.
In Avengers alternate universe fanfiction, Steve Rogers is quite popular. He represents the old - fashioned values and strong leadership, which can be a great contrast or a source of conflict in different universes. Thor is also well - liked. Imagining him in different settings, like a more modern or a more magical alternate universe, is really fascinating. Natasha Romanoff is popular too. Her skills as a spy and her complex past can be the basis for many engaging stories in alternate universes.
Naruto himself is very likely to have a significant role. He is the main character of the original series, and his strong will and unique abilities would be crucial in any time - traveling adventure. His determination to protect his friends and the ninja world would drive the plot.
Daenerys Targaryen remains popular in alternate universes as well. She might have a different set of dragons, perhaps ones with even more unique abilities. Her conquest of Westeros could be either more brutal or more benevolent, depending on the fanfiction writer's vision, and her relationships with other characters could be completely reimagined.