A really interesting fanfiction could be set in an alternate universe where Ash is born as a girl but has all the same adventures. This would be a different take on his character and how he interacts with the other characters in the Pokemon world.
There are some fanfictions that might explore Ash dressing as a girl in a different region. Maybe he has to do it to enter a tournament that only allows female trainers at first. He then uses this opportunity to learn new strategies from the female trainers he meets.
One possible fanfiction could be where Ash is forced to dress as a girl for a disguise in a Pokemon contest. In this story, his Pokemon have some really funny reactions to his new look.
One possible fanfiction could be where Ash has to dress as a girl for a mission in the Alola region (Sun and Moon setting). Maybe he needs to infiltrate a group that only allows girls. He would struggle at first with the new appearance but gradually get used to it and use his skills to complete the task.
One interesting fanfiction could be 'Izuku's Girlish Adventure'. In this, Izuku is forced to dress as a girl for a mission. He initially feels awkward but then uses it to his advantage to gather information. Another is 'The Girl - Izuku', where his transformation into a girl makes him see the world from a different perspective and he even befriends some characters who were previously unfriendly to him.
Well, I'm not sure of a specific title off the top of my head, but generally in these fanfictions, it's interesting to see how the characters around Naruto react. Do they recognize him? How do they treat him differently? It adds a whole new layer of depth to the Naruto universe. The concept often leads to humorous situations, like when Sasuke is completely baffled by this 'new girl' who seems oddly familiar.
One interesting fanfic could be where Harry has to dress as a girl for a mission. Maybe he's infiltrating a group that only allows female entry. In this fic, he might struggle with the new identity at first, like getting used to the clothes and the different way he's expected to act. It could add a whole new layer of humor and adventure to the Harry Potter universe.
Another plot could be that Ash's friends don't recognize him when he's dressed as a girl at first. This leads to some comical misunderstandings and situations, like his friends trying to flirt with him thinking he's a new girl trainer, while Ash is desperately trying to give them hints without blowing his cover.
There could be a female trainer who becomes Ash's rival while he's disguised as a girl. She might be initially dismissive of him, thinking he's just another girl trying to make it in the Pokemon world, but later be surprised when she discovers his true identity.
There might be a fanfiction where Ash dons the Latias costume as part of a disguise in a Pokémon contest. In this story, he has to not only look the part but also act like a Pokémon in some ways. This could lead to some really funny and heartwarming interactions with other characters.
One great 'Ash and Mega Sceptile' fanfiction could be about their adventures in a new, uncharted region. In this story, Ash might discover a unique way to Mega Evolve Sceptile that no one has ever seen before. It could involve a special bond between them that unlocks this new form of Mega Evolution, leading to battles against powerful, never - before - seen Pokémon.
Another plot is that Ash dresses as a girl as part of a bet or a challenge. Throughout the fanfiction, he discovers new aspects of himself or the Pokemon world that he wouldn't have otherwise. For example, he might learn about the unique challenges female trainers face.
The plot might involve Ash dressing as a girl due to a bet or a dare. In the Sun and Moon setting, he then has to go about his daily Pokémon - related activities like catching new Pokémon and battling, all while looking like a girl. This could lead to some humorous situations, like other trainers underestimating him. As the story progresses, he could prove that appearance doesn't matter when it comes to Pokémon training.