There could be some new characters introduced, like a local Pokemon trainer who becomes Ash's rival in Kalos. Maybe an old and wise Pokemon sage who gives Ash advice on training and understanding Pokemon better. And of course, the Gym Leaders of Kalos could have more interactions with Ash, as he is staying in the region.
Team Flare members might also show up again, this time with a new plan that Ash has to thwart. And there could be other Pokemon enthusiasts in Kalos that Ash meets, like a young girl who dreams of becoming a Pokemon coordinator like Serena. These characters would add more depth and variety to the fanfiction story.
Obviously, Ash himself. And his Kalos friends like Serena would probably be there. Clemont and Bonnie might also make an appearance as they were important parts of Ash's Kalos journey.
He could interact with Serena again. Since they have a history in Kalos, they might have new adventures together. Also, Clemont and Bonnie are likely characters he would meet up with. They could continue their friendship and maybe work on some new inventions together with Clemont, or have fun times with Bonnie and her love for Pokémon.
The main characters would surely include Ash. In the context of Kalos, his Pokémon like Pikachu are also key characters. Additionally, Serena, who has a special relationship with Ash during his Kalos adventure, is likely to be a main character. And there could be other trainers or characters that Ash interacts with in Kalos, such as Clemont and Bonnie, who might play important roles as well.
Well, one possibility is that Ash continues his Pokemon training in Kalos, facing new and stronger opponents. Maybe he teams up with old friends from Kalos to take on a new threat to the region.
Probably his friends from his adventures could show up. For example, Pikachu might be there as his constant companion. And maybe some of his human friends from the Pokémon world could be transferred to the high school setting, like Misty or Brock.
One possibility is that Ash decides to stay in Kalos to study Pokémon evolution in depth. Kalos has some Pokémon with very interesting evolution methods. He could team up with local Pokémon researchers and have adventures while learning more about how different Pokémon evolve under various conditions. This would not only expand his knowledge but also strengthen his bond with his own Pokémon.
Mega Evolution is a big part of the Kalos region. So characters like Diantha, the Kalos champion, could play a role. She might be observing the battles between Ash and Alain, and her presence could add pressure on them. Also, she could offer some insights into Mega Evolution that either Ash or Alain could use in their battles. Additionally, Clemont and Bonnie, who are friends with Ash, could also have some minor but important roles, like helping Ash with his Pokémon's gear or providing moral support.
In the 'smart ash in kalos fanfiction', Ash is surely one of the main characters as the title implies. His Pokémon, like Pikachu, Greninja, etc., would also be important characters. And perhaps some of the friends he makes in the Kalos region, like Serena, Clemont, and Bonnie, would be main characters as well. They could interact with this'smart Ash' in different ways, with Serena maybe being attracted to his newfound intelligence or Clemont being impressed and wanting to learn from him.
Serena could be one of the main characters in the harem. She has a close relationship with Ash already in the original series. Also, Miette might be included as she showed interest in Ash. And Shauna could also be part of it as she was always friendly towards Ash during his Kalos journey.
Obviously, Ash would be one of the main characters. There might also be his Pokémon like Pikachu. And he could meet new friends in Kalos like Serena, who often accompanies Ash in the official Kalos storyline.
Well, obviously Ash is one of the main characters. His Pokémon are also key characters in these fanfictions. They are the ones that show his strength through battles.