Yes, there are likely to be such fanfictions out there. The Harry Potter and Pokemon universes are both extremely popular, and fans often like to combine different fictional worlds in fanfiction. You can try searching on fanfiction websites like Archive of Our Own or FanFiction.net.
One idea could be that Naruto discovers a strange portal that transports him to the Pokemon world. Since he has his ninja skills, he quickly adapts. He might start by befriending Pikachu, as it's one of the most iconic Pokemon. His goal could be to become a Pokemon master, using his determination from being a ninja.
One common theme is power. Both Naruto characters and legendary Pokemon are known for their great power. So, in the fanfictions, there's often a focus on how the combined power of Naruto characters and Pokemon can be used, whether it's for fighting villains or protecting their worlds.
The plot could involve Naruto being on a quest to find all the Legendary Pokemon. Since he has that never - give - up attitude from his own world, he would face all the challenges in the Pokemon world head - on. He could use his chakra to enhance the abilities of the Pokemon he teams up with, creating a whole new power dynamic in battles.
Yes, there is. The world of fanfiction often combines different popular franchises. Naruto and Pokemon are both highly popular, so it's not uncommon for fans to create stories where the two universes intersect. These fanfictions can range from simple crossovers where Naruto characters encounter Pokemon, to more complex stories that blend the elements of both worlds like ninja using Pokemon in battle or having Pokemon in the Hidden Leaf Village.
One popular 'naruto and legendary pokemon fanfiction' is 'Naruto: The Pokemon Trainer'. In this story, Naruto discovers a world of Pokemon and starts his journey as a trainer while still having his ninja skills. It's really interesting to see how he combines his shinobi abilities with Pokemon training.
One possible plot for this fanfiction is that Naruto is transported to the Pokemon universe while on a mission. There, he discovers he has an affinity for training legendary Pokemon. He meets Pikachu first and they form a bond. As he travels, he encounters legendary Pokemon like Articuno. He uses his Naruto - style combat skills to earn the respect of these Pokemon. Eventually, he has to face a powerful villain who wants to use the power of the legendary Pokemon for evil. Naruto, with his new Pokemon friends, battles to save both worlds.
One interesting crossover could be Naruto having to team up with a Legendary Pokemon like Mewtwo. Imagine Naruto's speed and combat skills combined with Mewtwo's psychic powers. They could face off against powerful villains from both the Naruto and Pokemon universes. Another could be a story where Naruto discovers a Legendary Pokemon egg and has to protect it while on a mission.
It could be Team Rocket - style villains who want to capture Naruto because they think he has some special power that can help them control Legendary Pokemon. They might try to trick him or set traps for him.