One possible story could be that Ash is hit by a strange Pokémon attack that turns him into a Pichu. As a Pichu, he has to rely on his Pokémon friends in a whole new way. Pikachu, for example, might take on a protective role, guiding Ash - now a Pichu - through the challenges they face. And Ash would have to learn to control his new Pichu abilities like using Thunder Shock in a more instinctive way since he's now in a Pokémon's body.
Yes. The Nagatoro manga reached its end, giving fans a sense of closure. There might be some mixed feelings among readers, but the final chapters tied up loose ends.
One common theme could be friendship. Pichu might form strong bonds with other characters in the fanfic. Another theme could be growth, as Pichu may develop new skills or a deeper understanding of the world around it.
Yes, the Nagatoro manga has ended. It might have left fans with a mix of emotions, but it provided a definitive conclusion to the tale that had been unfolding.
You can try fanfiction websites like FanFiction.net or Archive of Our Own. These platforms have a large collection of Pokémon - related fanfics, including 'ash pichu fanfic'. Just use the search bar on the website and type in 'ash pichu fanfic' to find relevant stories.