Hermione would also be important. She could help Harry research and understand his heritage better, using her vast knowledge of magic and Hogwarts library resources.
Obviously, Harry himself is the most important character. His journey of learning about his heritage is at the core of the story.
Dumbledore is likely to play a crucial role as well. He might be the one guiding Harry in some way, or he could be withholding certain information about Harry's heritage that, when revealed, could change the course of the story.
In some fanfictions, there could be entirely new characters created just for the purpose of guiding Naruto in his journey to learn about his heritage. These characters could be mysterious hermits or powerful warriors from a forgotten era who hold the keys to unlocking Naruto's true identity.
Well, one possible plot development could be that Harry quickly adapts to his new - found heritage and uses it to gain an edge in his magical studies at Hogwarts. Maybe he discovers some long - lost family magic that gives him an advantage in Defense Against the Dark Arts.
Well, one possible plot development could be that Naruto immediately starts training in the unique abilities related to his heritage. For example, if his heritage involves some special jutsu, he might quickly master it and use it to gain recognition in the village. This could change his relationship with his peers as they see him in a new light.
Obviously, Harry Potter himself would be the central character. His friends like Hermione and Ron would probably also be there, as they often play important roles in his life and growth. Maybe some of the teachers like Dumbledore or McGonagall could also be involved to guide Harry in learning these new 'facts of life'.
Obviously, Harry Potter is the main character as the title implies he is the one learning magic early. But there could also be Hermione and Ron. Hermione might be intrigued by Harry's newfound knowledge and Ron could be both a bit jealous and in awe of Harry's early magical abilities.
One possible plot twist could be that his heritage is linked to an enemy he thought was unrelated. So he has to reevaluate his views on the whole conflict.
Obviously, Naruto himself is a key character as the story is about him learning his heritage. His mentor, like Kakashi, could also play an important role. Kakashi might notice some strange things about Naruto's abilities and start to suspect that there's more to his heritage. Then he could guide Naruto in the discovery process.
Obviously, Harry Potter himself is a very important character as the story revolves around him learning family magic. His friends like Hermione and Ron might also be important as they could support or help him in his journey of learning this magic.
In this fanfiction, Luna Lovegood could be an interesting addition. She might have some unique insights into Harry's metamorphmagus ability since she often has a different perspective on magic. The Weasley family as a whole could also be involved. Mrs. Weasley might be worried about Harry's new ability and try to mother him, while the twins could see it as an opportunity for some pranks or to develop new magical products. And then there's Hagrid, who would surely be there to offer his big - hearted support.
A previously unknown family member could be an important character. For example, an older cousin or an aunt who has been in hiding due to some dark secret related to the family's heritage. They could appear and help Harry navigate the complex world of his family's past, teaching him things that his parents were unable to before their untimely deaths.