I'm not sure specifically as there could be many different plots in this fanfiction. It might involve the adventures of the trainer in the Kalos region, encounters with new Pokemon, and the journey to become a Pokemon master.
I don't know for sure as it's a fanfiction. But it could be a young trainer, perhaps based on the player character in the games. Maybe there are also some unique NPCs created by the fanfiction author.
Serena is also very popular. Her relationship with Ash and her own growth as a Pokemon trainer add depth to the stories. She has her own dreams and goals in the Kalos region, which makes her a great character to follow in fanfiction.
One interesting plotline could be a trainer's journey to discover a rare and powerful Pokemon in the Kalos region. They might face many challenges along the way, like battling against powerful trainers who also seek the same Pokemon.
One great aspect of 'Pokemon Ash in Kalos Fanfiction' is the new adventures it presents. Ash's journey in the Kalos region in fanfiction often has unique twists. For example, the fanfic writers might introduce new Pokemon that Ash befriends in ways different from the original series. It also allows for different character developments, like Ash becoming more strategic in battles.
Froakie is quite memorable. Its evolution line into Greninja has a cool and ninja - like aesthetic. In a fanfiction, it could be the trusty partner of the main character, using its speed and unique moves to get out of tricky situations. Another one is Sylveon. It's so cute and fairy - type, which adds a new element to the Kalos region. It could be used as a symbol of kindness and friendship in a story.
May could fit into Kalos by participating in local Pokemon events. For instance, she could enter the Pokemon showcases in Lumiose City. Her unique style and skills would make her stand out, and she'd become a part of the Kalos Pokemon community.
There's also a fanfiction called 'Ash in Kalos: A New Beginning'. This one focuses on Ash arriving in Kalos and how he adapts to the new region. It has some great character development for Ash, as well as for his Pokemon. The story is well - written and has some interesting takes on the Kalos gym battles.
I would recommend 'Ash's Kalos Adventure Redefined'. It has a great plot where Ash discovers a hidden power within one of his Pokemon. It's really engaging.
In this fanfiction, Ash and May could be on separate adventures in Kalos at first. But then, they cross paths when they both get involved in a mystery related to a rare and powerful Pokémon in Kalos. They have to put their heads together, along with their Pokémon, to solve the mystery and protect the Pokémon from those who would use it for bad purposes.