If reincarnated as an Eevee, Ash's personality could have some interesting changes. Since he'd be in the body of a Pokémon, he might develop a more instinctual side. He'd have to rely on his natural Pokémon senses more. His adventurous spirit would likely remain, but it could be tempered by the fact that he now has to worry about things like being caught by a trainer he doesn't like. He might also become more empathetic towards other Pokémon, as he'd now be one of them.
His personality might become more cautious. As an Eevee, he's smaller and more vulnerable compared to being a human. So he'd probably be more careful when approaching new situations or other Pokémon. But his determination from his previous life as Ash would still be there. He'd still be eager to prove himself and become strong, just in a different way.
In a fanfiction where Ash is reincarnated as an Eevee, his journey would be very different. Firstly, his physical abilities would be limited to what an Eevee can do. He couldn't just run around freely like a human. However, his knowledge of Pokémon battles and the world in general would be a huge advantage. He could potentially form alliances with other Pokémon that he knew were strong from his past life. Also, his relationship with Pikachu would be interesting. Would Pikachu recognize him? And how would Ash, as an Eevee, interact with Pikachu now?
Well, perhaps Pikachu would go on a heroic quest to rescue Ash. It might team up with other Pokémon like Charizard. They could follow the kidnappers' trail, facing various challenges along the way, like battling wild Pokémon or getting through difficult terrains.
His personality might become more carefree like Luffy's. He would probably be more laid - back and not worry as much about formalities.
He'd probably be more reserved. Kakashi is not as boisterous as some others, so Naruto might pick up on that. For instance, he might not shout as much about becoming Hokage right away.
If turned into a kid, Deadpool's personality would lose some of its edge. He'd be more impulsive in a child - like way, not thinking about the consequences as much as he does as an adult. His love for chaos would remain, but it would be more like a child's playfulness. He might also be more vulnerable in a sense, showing emotions more openly like a kid does.
His personality could also develop in new ways. Since the RWBY world has different social structures and challenges, Naruto could become more diplomatic. He'd have to interact with different races and factions, like the Faunus. So, he might learn to be more understanding and empathetic towards those with different backgrounds, which could add new layers to his already complex personality.
At first, Ash and Eevee might be a bit cautious around each other. Ash is excited to have caught a new Pokémon, but Eevee is in a new and strange environment. As they start training together, they build trust. Eevee might learn new moves from Ash's guidance, and Ash learns more about Eevee's unique abilities.
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.
Ash's personality could become more diplomatic as a girl. In the Pokémon world, he would need to navigate different social situations. As a girl, he might use charm and persuasion more often. His love for Pokémon would still be there, but he could show it in a more gentle way. For example, instead of just being excited about catching new Pokémon, he might focus more on the well - being and happiness of the Pokémon he already has.
Ash would probably become more patient. Rangers often have to wait and observe Pokémon in their natural habitats. This is different from his Trainer days where he was more focused on quick battles and leveling up his Pokémon. He'd also be more diplomatic, since he'd need to work with other Rangers and people in the Pokémon world who might have different opinions on conservation and Pokémon management.