Most likely, Harry Potter will still be a main character, but perhaps with a different personality or set of skills. Hermione Granger and Ron Weasley may also be main characters, but they could be given new story arcs. There might also be new characters introduced that play important roles in the fanfiction.
Harry Potter is almost surely a main character, but in this new look fanfiction, he could be more of a mentor figure rather than just a student. Hermione might be exploring a new area of magic that changes her role in the story. Ron could be involved in some international wizarding relations, which would give him a whole new dimension. And there could be a new character, say a transfer student from a far - off wizarding school, who becomes a central part of the story, bringing in different cultural aspects of the wizarding world.
Obviously, Harry Potter himself would be the main character as the story is centered around his new look. His friends like Ron and Hermione would also be important characters as they would react to his new look and help him deal with any consequences. And there could be new characters introduced, perhaps a mysterious wizard who is somehow related to the cause of Harry's new look.
He could have a more modern wizard look, with a sleek black robe and a new wand design.
It might make him more confident if he looks more stylish or powerful.
It's likely that Harry Potter himself would still be one of the main characters. Hermione and Ron would probably also play important roles. However, there could be new characters introduced as well that are central to the new order concept.
Obviously, the marauders themselves - James Potter, Sirius Black, Remus Lupin and Peter Pettigrew. They would be central to the story as they are the ones the fanfiction is named after.
There could be the children of the original characters. For example, Harry Potter's son or Hermione Granger's daughter might be main characters.
Harry Potter himself is likely to still be a main character. He's the face of the series. Hermione and Ron will probably also be important. But new characters might be introduced too, perhaps a mysterious new student or a powerful wizard from a far - off land.
Typically, the children of the original characters like Harry Potter, Hermione Granger, and Ron Weasley are main characters. So, you might have Albus Potter, Rose Granger - Weasley, etc. They inherit the legacies of their parents and often have to live up to great expectations.
Obviously, Harry Potter himself would be one of the main characters. His friends like Hermione Granger and Ron Weasley might also be involved. There could also be American wizards or witches that are central to the story, perhaps a young and brave New York wizard who teams up with Harry.
Well, it's likely that Harry Potter himself could still be a main character, perhaps as a mentor to the new generation. His children might also be main characters, as they carry on the Potter legacy at Hogwarts.