Let's consider the relationship with Voldemort. In this fanfiction, Voldemort might see Fem Harry as a way to get to Narcissa or use her as a pawn in some way. But Fem Harry, with Narcissa's influence, could be more prepared to face him. Her relationship with the Order of the Phoenix would also be altered. Some members might be distrustful of her new family situation, while others might see it as an opportunity to gather intelligence from the inside. And Narcissa herself would have a very maternal relationship with Fem Harry, which would be a huge change from Harry's original lonely and often - unloved state in the canon story.
In some fem Harry Potter fanfics, Narcissa can become more of a protector. For instance, if the story involves a female Harry Potter who is in danger, Narcissa might step up in ways she didn't in the original series. She could be more assertive in using her influence within the Death Eater circles to safeguard Harry.
Her relationship with Ron and Hermione would be different. Ron might be more easily charmed by her siren side at first, which could cause some tension. Hermione would be both curious and a bit worried about her new abilities. She might try to research sirens more to help Harry control her powers.
His relationship with his enemies like Voldemort would also be affected. If Regina has some sort of power or influence over Harry, Voldemort might see him as an even greater threat or an easier target. Harry might also have different ways of defending himself, influenced by Regina's methods or the new environment he's in. For example, Regina might have her own way of dealing with dark magic that she teaches Harry, which changes how he approaches Voldemort and his Death Eaters.
His relationship with Sasuke would be different. Sasuke might view Naruto's connection with the Fem Kyuubi as a new source of power and be more wary or even jealous. But Naruto could use his new situation to try and bring Sasuke back to the right path earlier.
One possibility is that it could explore a very different Hogwarts experience for Fem Harry. With Narcissa as her adoptive mother, she might have access to different resources and a different social standing in the wizarding world. Maybe she'd be more connected to the Slytherin crowd from the start, which could lead to some interesting friendships and rivalries. Also, Narcissa could teach her more about pure - blood traditions, but Fem Harry might struggle with some of the more discriminatory aspects, adding an interesting internal conflict to the story.
His relationship with Draco could become more of a brotherly one. At first, Draco might be resentful because Harry is suddenly part of his family, but as they grow up together, they start to understand each other better. They could end up protecting each other from the threats in the wizarding world, like the Death Eaters.
Her life would change drastically. She'd be living in luxury and surrounded by all the trappings of royalty. She'd have to learn proper etiquette and protocol. For example, she'd have to know how to curtsey and address different members of the royal family correctly.
If the Avengers adopted Harry Potter, their lifestyle would transform in numerous ways. Firstly, their communication methods could change. Harry might introduce them to magical ways of sending messages like the Patronus message. In terms of daily activities, they would need to factor in Harry's need to study magic. So, they might set up a special area for him to practice spells and study his textbooks. Their mission planning would also be different. Harry's knowledge of different kinds of magic could provide new strategies for taking on enemies. For instance, he could use the Invisibility Spell to gather intelligence or use magical traps to capture villains. And the Avengers would have to learn about the wizarding laws and customs to ensure Harry doesn't get into trouble with his own world while living with them.
If Harry Potter is adopted by the Autobots in fanfiction, the story would take on a whole new dimension. Harry would be exposed to a completely different way of life and technology. His understanding of the world would expand beyond the magical realm. He might use the Autobots' technology to improve his magical devices. And the Autobots could use Harry's knowledge of magic to their advantage in their own battles. This would also introduce a new element of mystery and excitement to the story as the two different worlds collide.
The relationship between Harry and Snape would be completely transformed. In the original timeline, Snape had a lot of pent - up anger towards Harry because of his resemblance to James. But if time was turned back, Snape might see Harry as an opportunity to right the wrongs of the past. He could become a mentor to Harry, teaching him advanced potions and dark arts defense in a way that Dumbledore never did. This would also change Harry's perception of Snape from a bitter enemy to a trusted ally.