Well, perhaps Natsu turned into a girl could lead to a story where she has to go undercover as a female in an all - female magic group. This would force her to learn about the different culture and magic techniques of women - only groups. Or maybe she gets involved in a beauty contest in the magical world by accident, and her friends from the guild have to help her out while she's in this new form.
One idea could be that Superboy is hit by a strange alien device that changes his gender. He then has to deal with the new physical limitations and social expectations while still trying to be a hero. For example, he might struggle with the different way people treat him as a girl and how to use his powers in a more feminine body.
One plot idea could be that Link, as a girl, has to hide her true identity in a world that doesn't expect a female hero. She could face challenges like being underestimated at first but then prove herself in battles. Another could be that she forms unique relationships with the other characters, like a different kind of friendship with Zelda. Maybe she also has to deal with newfound emotions and how they affect her heroic duties.
One interesting plotline could be Natsu trying to adjust to the new physical form while still having the same adventurous spirit. For example, Natsu might initially struggle with wearing different types of clothes that are more suitable for a female body. Another plotline could be how Natsu's friends react. Some friends might be shocked at first, but then quickly accept and help Natsu through this strange transformation. There could also be a plotline where Natsu discovers new abilities or sensitivities that come with being in a female form.
One idea could be that they go on a quest together to find a rare magical item that is said to have the power to save Galuna Island from a new threat. Another could be that the girl from Galuna has a special power that Natsu needs to unlock his own new level of magic. Maybe they start off as rivals, competing to be the best in a magical tournament but then gradually fall in love as they discover more about each other.
One plot idea could be that the crossdresser, after being turned into a girl, has to navigate a new social life. For example, they might struggle to fit in with the girls at school or work. Another idea is that they discover new aspects of themselves, like different fashion tastes or hobbies that they didn't explore before. They could also face challenges in their relationships. Maybe their friends don't recognize them at first and they have to re - establish those friendships.
A possible plot is that Ron - turned - girl gets involved in a magical beauty pageant that has some dark secrets behind it. She enters it thinking it's just a bit of fun but soon realizes there's more at stake. This could lead to her using her typical Ron - like courage and quick thinking to expose the secrets. Additionally, her romantic interests might shift. Instead of pining after Hermione in the same way, she could develop feelings for a different character, perhaps someone from another house who is intrigued by this new version of Ron.
In this fanfiction, perhaps Dipper getting turned into a girl is part of a curse. The curse was placed by an ancient being that Dipper accidentally awakened. As a girl, Dipper finds that she has a stronger connection to the nature in Gravity Falls. She can communicate with animals in a different way and understand the plants better. This new connection helps her in her quest to break the curse. However, she also has to face the fact that some of the boys in town, who used to be her friends or acquaintances, now act differently around her. It's a whole new world for her to explore and understand.
One idea could be that Natsu discovers a new and rare type of fairy magic that he has to learn to control. Another could be Natsu getting involved in a fairy war and having to choose a side. Maybe he could also meet a fairy who has the power to grant wishes and he has to decide what to wish for.
One plot idea could be that Dean, as a girl, has to deal with the different ways people treat her in the hunting world. Maybe some monsters underestimate her at first, but she quickly shows them she's still as tough as ever. Another idea is that she has to navigate her relationships with Sam and Castiel in a new way, especially any potential romantic feelings that might change or emerge because of her new form.
One plot idea could be that Natsu accidentally discovers Mirajane's secret hobby, like painting. As he tries to help her show her work, they grow closer. Another could be a mission where they get separated from the rest of the guild and have to rely on each other for survival, leading to a realization of their feelings. Or perhaps a magic - induced amnesia situation where Natsu forgets everyone but Mirajane is determined to make him remember their relationship.