One possible plotline could be that fem Harry is intrigued by Orochimaru's unorthodox and powerful jutsu. She might start to study his techniques secretly, seeing them as a way to gain power to protect herself in the dangerous wizarding world. This could lead to her getting into trouble as Orochimaru's methods are often considered dark and unethical in the context of the magical world.
One possible way could be in a crossover fanfiction where the magic systems of the Harry Potter universe and the ninja world of Orochimaru are combined. For example, Orochimaru might be interested in the magic of the Harry Potter world and try to study it. Maybe he could see the magic there as a new source of power or knowledge. Another aspect could be a character - perhaps a wizard - being sent to the Naruto world and having an encounter with Orochimaru, and through that, a connection between the two universes is established.
Hermione could be one of the main characters. She might be suspicious of Orochimaru's teachings and try to convince Harry that it's wrong. She would be constantly researching about Orochimaru and the type of magic he's teaching Harry to prove her point.
Well, one possible plot could be that Orochimaru somehow finds his way into the Harry Potter universe. He might be interested in the unique magic there, like the Elder Wand or the Philosopher's Stone. He could try to use his ninja skills and devious ways to steal these powerful magical items, and Harry and his friends would have to stop him using their own magic.
There could be a conflict between Harry and the existing wizarding order. The Ministry of Magic might view Harry as a threat because of his connection to Orochimaru. They would be worried that he might bring dark magic into the wizarding world. Harry would then have to fight against the prejudice and suspicion of the wizarding community, while also trying to figure out his own identity and loyalties.
A connection could be made through a shared interest in immortality. In the Harry Potter universe, there are things like the Philosopher's Stone that can grant immortality, and Orochimaru is constantly seeking ways to cheat death in his own world. A fanfiction could explore how Orochimaru hears about the Philosopher's Stone and tries to get his hands on it, which would bring him into conflict with the Harry Potter characters.
I'm not aware of any such official 'Harry Potter is Orochimaru fanfiction'. Harry Potter and Orochimaru are from two completely different fictional universes - Harry Potter from the wizarding world created by J.K. Rowling and Orochimaru from the Naruto universe. It's possible some very niche and non - official fan - created works might exist, but it's not a common or mainstream concept.
Her character could develop a more morally ambiguous side. Since Orochimaru is known for his dark deeds, being a fan might make fem Harry more willing to consider actions that are not strictly 'good'. For example, she might be more likely to use underhanded tactics in a fight.
His personality would be a mix of his original self and Orochimaru's influence. Harry is inherently brave, but Orochimaru's devious nature might make him more cautious and calculating. He might be less trusting of others, always suspecting ulterior motives. And he could also be more ruthless when it comes to achieving his goals, having learned from Orochimaru that sometimes you have to be cruel to get what you want.
Well, if Harry Potter was raised by Orochimaru, his magic might develop in a rather different way. Orochimaru is all about experimentation and pushing limits. He might encourage Harry to explore the darker aspects of magic earlier. Harry could end up with a more unorthodox style of spell - casting, perhaps mixing some of the dark arts with traditional wizardry. But he would also have to fight against Orochimaru's more immoral teachings to stay true to his own values.