Well, it could potentially have the main character from Pokemon Red, like Red himself. He would be the one exploring the Alola region in this fanfiction.
One popular character could be the local Alola Pokemon Professor. He is often seen as a source of knowledge, guiding trainers in their journey in 'pokemon red alola fanfiction'.
A Litten might be a good choice for Serena. It has a fiery personality and could bring a new dynamic to her team. With proper training, it could become a powerful Fire - type Pokemon in battles against water - type opponents in Alola.
Professor Kukui is another common character. He serves as a guide and mentor to Ash in the Alola region. He might provide Ash with new Pokémon knowledge, especially about the unique Alola Pokémon species. And of course, there are the various Pokémon trainers that Ash meets and battles in the Alola region. These trainers can range from novice trainers just starting out to more experienced ones who pose a real challenge to Ash.
Gladion is also popular. His edgy and mysterious personality can add a lot of intrigue to a story. You could write about his past, his connection to the Aether Foundation, and his journey to become a stronger trainer. Maybe in your fanfiction, he teams up with the main character for a special mission.
Well, obviously Ash is one of the main characters. He's the protagonist of the Pokémon series and his journey in Alola is the focus. Pikachu is also a main character as Ash's loyal Pokémon partner. In Alola, there could be new friends like his classmates from the Pokémon school, such as Kiawe, Lillie, and Sophocles, who would also play important roles in the fanfiction.
I don't know for sure without reading it, but probably the trainer who is on the Alola journey, and maybe some of the well - known Alola characters like Hau or Lillie.
A common theme in such fanfictions could be Ash's adventures in Alola while building relationships with different characters. Maybe he forms special bonds with his Pokémon and the people around him in a more romantic or friendship - deepening way.
One great 'Pokemon Ash Alola' fanfiction is 'Ash's Alolan Adventure'. It has Ash making unique friendships in Alola and facing new Pokemon challenges. The story really captures the essence of the Alola region with its beautiful descriptions.
There could be a girl named Lillie as a main character. She is shy but has a strong bond with her Pokemon. At the high school, she could be the one who is always there to help out her classmates when their Pokemon get into trouble or when they need advice on training.