One interesting plot could be how Harry, now as a girl, has to deal with the different social dynamics in Hogwarts. For example, she might face different expectations from teachers and peers. Maybe she forms new friendships with female characters in a way that Harry as a boy never did before.
In the 'Harry Potter turns into a girl fanfic', an exciting plot development could be her participation in the Tri - Wizard Tournament. As a girl, she might face different challenges and advantages. Some of the tasks could be designed in a way that takes into account her new gender. And her relationship with Cedric Diggory could be completely different. There could be more of a romantic tension, or perhaps a sister - like bond, which would be a whole new aspect to explore in the story.
One possible plot development is that Harry's friends initially don't recognize him when he's mistaken for a girl. This could lead to some really funny misunderstandings. They might start flirting with him, thinking he's a new girl in school. And Harry has to find a way to reveal his true identity without causing too much chaos among his friends.
Well, a possible plot development is her struggle with identity. Since she has the memories of Harry but is now a girl, she may have an internal conflict. She might wonder if she should still follow the same path as Harry did in the original story. Also, in terms of magic, she could discover new ways of using magic that were perhaps not explored by Harry because of the different way she experiences the magical world as a female. For instance, she could have a special connection with certain female - centric magical creatures or spells that are more attuned to her new gender. And her presence as a girl could inspire other female characters in the wizarding world to be more assertive and strive for more equality in magic education and other aspects.
One idea could be that Harry's transformation into a monster girl makes him/her (depending on how the transformation affects gender identity) discover a whole new world of magical creatures that were previously hidden from normal wizards. He/She could form unique bonds with these creatures and use their newfound abilities to solve mysteries in the wizarding world.
One interesting plot could be Harry having to deal with the different social expectations placed on girls. For example, in the wizarding world, there might be different rules or attitudes towards female students in Hogwarts. He might struggle with how to act in a way that is considered 'appropriate' for a girl while still maintaining his own identity.
A great plotline could be that Harry, now a girl, has to navigate the world of wizarding fashion and etiquette which she previously ignored. She might be forced to attend more social events at Hogwarts, like balls or tea parties, where she has to learn proper behavior. And she could also use her new identity to her advantage when it comes to spying on the Death Eaters. They might underestimate her because she's a girl, but she could outwit them.
Well, perhaps one interesting development could be Harry exploring the new powers and responsibilities that come with being a lord. He might use his new status to reform the wizarding world in ways he couldn't before as just a student.
One interesting plot development could be Clary struggling to control her new vampire instincts while still trying to protect her friends. She might have a hard time dealing with the thirst for blood and not wanting to harm the people she loves.
Another aspect could be that Naruto's baby form has some unique abilities or auras. Maybe his presence as a baby has a calming effect on some of the more aggressive characters in the Naruto world. His friends could also discover new things about his past or his family through his baby state, like finding a hidden mark on his body that gives clues about his heritage.
Well, one interesting plot could be Naruto, as a female, having to deal with different social expectations in the ninja world. For example, she might face more challenges in being taken seriously as a strong fighter since there are some gender biases in the original Naruto world. Another could be her new relationships with other characters. Maybe she forms a different kind of bond with Sasuke, not just as a rival but in a more complex, perhaps more emotionally charged way.
One interesting plot could be Harry struggling to fit in with the Slytherin ideals at first. He might be constantly at odds with some of the more traditional Slytherin values like pure - blood supremacy. But then he could gradually change the house from within, making his Slytherin peers see that not all Gryffindor traits are bad and vice versa.