Squirtle - girl could be a key character. Her water - based abilities would be useful in many scenarios, like putting out fires or creating barriers. And she has a fun, mischievous personality that could lead to some humorous moments in the fanfiction. Plus, she could form a unique bond with Naruto based on their mutual love for adventure and getting into scrapes.
Bulbasaur - girl might be a great choice too. Her connection with nature and plant - based attacks could add an interesting dynamic. She could help Naruto understand the Pokemon world better, especially when it comes to things like finding herbs or dealing with forest - related challenges. There could also be a fiery - tempered Charmander - girl who provides a contrast to Naruto's more easy - going nature and has her own set of powerful fire - type attacks.
The main characters could be Naruto, and a Sylveon Girl. Sylveon is known for its loving and kind nature, and as a Pokegirl, she could be the heart of the group. Then there could be a Lucario Girl. Lucario is a very powerful and intelligent Pokemon, so as a Pokegirl, she would be a great fighter and strategist, working well with Naruto's own combat intelligence.
One of the main characters could be Fleur Delacour. Since she's from Beauxbatons, she might be the one to first interact with Naruto. She could be curious about his strange abilities and help him adjust to the school. Another could be a male student at Beauxbatons who is initially jealous of Naruto getting all the attention but later becomes his friend after seeing his true character.
There could be a leader of the horde. This character might be initially skeptical of Naruto but later comes to respect him. Another character could be a young member of the horde who looks up to Naruto as a role model and wants to learn from him.
Maybe there are new characters created specifically for this fanfiction. They could be local inhabitants of the wet area, such as a water nymph - like character who has knowledge about the secrets of the place and either helps or hinders Naruto's journey.
Lelouch could be a main character. Since he is a key figure in the Code Geass world which has Britannia. He and Naruto might start as rivals due to their different approaches to justice but later become allies. Suzaku could also be involved. He might be initially suspicious of Naruto but come to respect him as Naruto shows his good intentions in the Britannian world.
Hinata could be one of the main characters. She might support Naruto in his efforts to rebuild the Whirlpool Village, both morally and with her Byakugan skills which could be useful for scouting and security.
An elf who adopts Naruto could be a main character. This elf might be an elder with great wisdom and magical powers. They see something special in Naruto and take him under their wing. Another character could be an elven child who becomes Naruto's friend. They teach each other about their respective worlds and grow together.
Sakura would be a likely main character. She is a skilled medical ninja, so she could play a crucial role in ensuring the health of those involved in the repopulation efforts. For example, she could develop new medical procedures to help with childbirth or deal with any potential health issues that might arise during pregnancy.
Gaara could be a main character. Since Naruto has a connection with him already, Gaara could play a big role in helping Naruto adjust to life in Suna. Maybe he becomes like a brother to Naruto in this new setting.
Well, I think Zabuza could be a key character. Maybe he has some unfinished business in Wave and Naruto's arrival stirs things up. And the villagers of Wave, like Tsunami, could be main characters too. She could provide Naruto with a place to stay and offer motherly advice. There could also be new, original characters created specifically for this fanfiction, like a young ninja in Wave who looks up to Naruto.