If Ash turns into a legendary Pokemon in a fanfic, his personality would be greatly influenced. He might become more patient, as legendary Pokemon have a long lifespan and a different perspective on time. He could also develop a sense of superiority, but at the same time, he would still have his kind heart. For example, he might be more hesitant to engage in battles with regular Pokemon, seeing them as much weaker. But when it comes to protecting the weak, he would be even more determined. His relationship with his friends would also change, as they would have to adapt to his new self, and he would have to find a balance between his new identity as a legendary Pokemon and his old self as Ash.
His confidence might increase a great deal. Since legendary Pokemon are often seen as very powerful, Ash in his new form would feel more capable. He might become more solitary too, as some legendary Pokemon are known to be lone creatures.
If Ash were to turn into a Pokemon in a fanfic, his personality would surely be affected. He's used to being in control as a trainer, but as a Pokemon, he'd have to learn to follow others' commands or work within a group. His once outgoing and friendly nature might become more cautious. He'd have to be more aware of predators and threats. And his competitive spirit might take on a different form. Instead of competing in trainer battles, he'd be competing in Pokemon - on - Pokemon battles, which could make him more aggressive or strategic depending on the Pokemon he turns into.
If Ash becomes a legendary Pokemon in a fanfic, it would change the whole Pokemon world dynamic. He might be hunted by evil organizations who want to use his power. On the other hand, he could also use his new form to protect the Pokemon world better than ever. His friends would likely have a mix of reactions, from being amazed to being worried about losing the old Ash.
His relationship with Pikachu would be very different. They'd be more like equals now. Pikachu might even feel the need to protect Ash more. With his other Pokemon, they might be confused at first but then develop a stronger bond as they realize it's still Ash inside.
Well, Ash is known for his adventurous and curious nature. In Mewtwo's body, that adventurous spirit might be redirected. Instead of running around exploring physically, he might use Mewtwo's psychic powers to explore the minds of other Pokemon or discover hidden places in the psychic realm. His personality would also become more complex as he'd have to deal with Mewtwo's memories and emotions. He'd still be the same Ash at heart, but there would be an added layer of depth and thoughtfulness, perhaps a bit of melancholy too as he'd understand Mewtwo's pain of being created for the wrong reasons. And his interactions with other Pokemon and humans would be different. He might seem more intimidating at first because of Mewtwo's appearance, but as soon as he started to communicate, his friendly and helpful Ash - like personality would show through.
The story would become more about Ash adapting to his new form. He'd have to learn how to move, eat, and sleep like a Pokemon.
His personality might become more positive. Instead of being a bit of a schemer like he was with Team Rocket, he could become more helpful and honest. He might start to care more about others' feelings.
He might become more cautious. Usually, Ash is quite bold and rushes into things. But if he's in a Team Rocket - centered fanfiction, he'd likely be more careful as he's constantly surrounded by danger. For example, he'd think twice before challenging a new Pokemon or entering an unknown area.
Saitama's personality might not change that much at first. He's still likely to be laid - back. But he might become a bit more self - conscious about his appearance as a girl. For example, he might start to care more about his hair or the way his clothes fit.
Well, Batman as a kid in fanfiction would have a very different personality. His determination would still be there, but it would be mixed with a child's innocence. He'd be more likely to make mistakes based on inexperience, but also more willing to forgive and forget. His sense of humor might emerge more, as kids tend to find humor in different things. He could also be more vulnerable, which would make his relationships with other characters more complex. For example, his relationship with Alfred would become more of a father - son dynamic, with Alfred having to be more protective and nurturing.
If Ash becomes a female in the fanfic, his relationships with his Pokemon friends would also be different. His Pokemon might sense the change and some could be more affectionate, while others might be a bit confused at first. Regarding his human friends, his relationship with Gary would take an interesting turn. Gary might be more intrigued by this new Ash and could either be more competitive or try to help her adjust. And when it comes to Professor Oak, he might be more fatherly or have different expectations of Ash now that she is female, perhaps expecting her to focus on different aspects of Pokemon research or training.