Snape could also be a central figure. Maybe he discovers Harry's situation early on and has a change of heart. He could secretly guide Harry, teaching him things about magic and the wizarding world that he otherwise wouldn't know, all while still maintaining his aloof exterior.
A magical creature native to China could be a main character. Maybe a phoenix - like being but with unique Chinese characteristics. It could communicate with Harry Potter in some way and help him on his journey. It could have powers that are different from the magical creatures Harry is used to in the UK, and they could form an unlikely bond as they face the mysteries together.
Hermione could be one of the main characters. She would be very helpful with all her knowledge of spells and magic theory. She could assist Harry in planning the layout of the village and ensuring that everything is in order.
Hermione could be one. She might come to the forest to check on Harry and end up staying to study the unique flora and fauna which have magical properties. Another could be Hagrid. He loves all kinds of creatures and the forest is full of them, so he could visit Harry often and bring him supplies.
Hermione could be a main character. She might be initially skeptical about Harry singing muggle music, but then she gets interested in the cultural aspect of it and starts researching the history of the muggle music Harry likes.
There could be an original character who is a descendant of the Uchiha that somehow ends up in the wizarding world. This character could teach fem Harry Potter about the Uchiha ways. Also, Dumbledore could play a role as he always encourages Harry's exploration of different knowledge, and he might be curious about the Uchiha knowledge that Harry is so interested in.
Ron could also play a significant role. He could be initially shocked by Harry's revelation but then stand by his side. And perhaps there could be a new character, someone who has been observing Harry all along and has a hidden agenda related to his true self that is now exposed.
Dumbledore could still play a role, perhaps as a mentor from the shadows. Even though he's no longer alive in the original series, in fanfiction, his wisdom could be passed on through memories or portraits. He might offer cryptic advice to Harry about how to use his new power for the greater good and avoid the temptations that often come with lordship.
Hermione could be one of the main characters. She might be initially skeptical about Fem Harry Potter's newfound interest in stage magic but then get drawn into it when she realizes it can be a new form of knowledge. Another could be Ron, who might find it all a bit strange but still support Fem Harry Potter out of friendship.
Ron could also be the main character. He has his own courage and loyalty. He could be the one who has an unexpected connection with the poisonous snake, like being able to communicate with it in a special way that no one else can.
Ron and Hermione would surely be there. Ron might be a bit hesitant at first about Harry raising a dragon, but he would come around to help. Hermione would use her vast knowledge of magic and creatures to assist Harry in taking care of the dragon.