Ash's journey in an alternate universe fanfiction could be vastly different in many aspects. For starters, the geography of the world could be completely changed. There might not be the familiar Pokémon gyms in the same locations or even at all. The Pokémon themselves could have different evolution methods or not evolve at all. Ash would then have to figure out new ways to strengthen his team. Also, the cultural aspects related to Pokémon could be different. In the original, Pokémon battles are a big part of the culture, but in this alternate universe, it could be something else entirely, like Pokémon art competitions or Pokémon knowledge quizzes, and Ash would have to adapt his goals and strategies accordingly.
Ash could become a powerful villain in the alternate universe fanfiction. Maybe he has a different backstory that led him to the dark side.
It can change the character's motivation. For instance, Santana might be more focused on becoming a solo artist rather than part of a group in an alternate universe. This changes her arc as she has to fight different battles, like dealing with music producers alone instead of relying on the glee club support.
It would change his journey a great deal. Firstly, having a shiny Charmander would make him stand out more. Other trainers would be more likely to challenge him, either to prove themselves against someone with a rare Pokémon or to try and get his Charmander. Also, trainers with more experience might offer to help Ash train his shiny Charmander, which could lead to new training techniques. In Pokémon contests, his shiny Charmander would be a show - stopper, giving him an edge in those aspects of his journey as well.
He might become more open - minded. Realizing that there are countless ways his world could be different would make him less set in his ways. For example, he may start to consider alternative strategies in battles or ways to interact with his friends that he hadn't thought of before.
The meeting would likely give Ash a new sense of purpose. He might shift his focus from just winning battles and championships to something more grand, like protecting the entire Pokemon universe. He could also meet new and rare Pokemon through his connection with Arceus.
Ralts could make Ash more empathetic. Since Ralts is a psychic - type Pokémon that can sense emotions, Ash might become better at understanding the feelings of other Pokémon and people. This could help him in his journey to be a better Pokémon trainer.
First, come up with a unique concept for your alternate universe. It could be something like a world where ninjas use modern technology. Then, think about how the characters will be different. For Naruto, maybe he's not an orphan or he has different abilities. Next, plan out the plot. You can start with a small change in the Naruto universe and build on it. For instance, if the Uchiha clan was never massacred, how would that change the relationships and the overall story?
It may differ in the character arcs. In the original, Ash is mainly focused on becoming a Pokémon master. But in this different version, he could have other goals, like saving a particular endangered Pokémon species. His relationships with other characters might also be different. For instance, his friendship with Misty and Brock could be more strained or closer in new ways.
If Naruto travels to an alternate universe, his relationships would change drastically. For example, if he meets his friends' alternate versions, they might have different personalities. His relationship with Sasuke could be very different. Maybe in this new universe, Sasuke is a laid - back person instead of brooding. His bond with Sakura could also change. If she's a more confident and powerful ninja in the alternate universe, Naruto might see her in a new light.
In an alternate universe, their relationship could start as a friendship based on mutual respect. Felix might admire Bella's courage in the face of danger, and Bella could be intrigued by Felix's strength and loyalty to the Volturi. This friendship could gradually turn into a deeper emotional connection as they face various challenges together.