One possible plot could be that Harry discovers a hidden magical school in Japan. He has to adapt to the new culture and magic system there. Maybe he meets new friends who teach him about Japanese magical traditions and spells.
A new character could be an old and wise sensei - like wizard, Master Takeshi. He teaches Harry about the ancient Japanese magic arts. And there might be a group of mischievous students, like Hiro, Yuki, and Ryu, who at first give Harry a hard time but later become his friends.
Maybe Harry meets a group of magical creatures' protectors in Japan. They are dedicated to protecting the unique magical creatures in Japan, and Harry joins them in their adventures, learning a great deal about Japanese magical fauna along the way.
Well, it could be about Harry going to Japan for a magical exchange program. Maybe he meets new wizards there, discovers unique Japanese magical creatures, and learns different types of magic that are specific to Japan.
Yes, there are quite a few. You can start by looking on popular fanfiction websites like Fanfiction.net or Archive of Our Own. Some stories might explore how Harry's experience at Durmstrang would be different from Hogwarts, like different classes and a more strict regime.
In fanfiction, if Harry attends Beauxbatons, he might experience a very different magical education. The curriculum at Beauxbatons could be more focused on certain aspects like etiquette and different forms of magic compared to Hogwarts. He could make new friends from different backgrounds and learn different magical traditions. Maybe he'd have to adapt to the more refined and formal environment of Beauxbatons.
One common theme is the culture shock. Harry coming from Hogwarts to Durmstrang would experience a very different magical education system. Another theme could be the relationships he forms with new classmates. They might be more competitive or have different loyalties.
The story changes in many ways. Firstly, the setting is different. Beauxbatons has a more European charm compared to Hogwarts. Harry would be exposed to different kinds of magic and spells. His relationships with other students would be different too. He might not have the same rivalries as he had at Hogwarts. Instead, he could form new alliances based on the different values at Beauxbatons.
Harry might adapt by learning the language first. Since Japanese is different from English, he'd have to study it to communicate with his classmates and teachers. He may also adapt to the different school uniforms. Japanese wizarding schools might have more traditional - looking uniforms compared to Hogwarts. And he would adapt to the new types of magic lessons. For example, if they focus more on group harmony in magic - making, Harry would need to learn to work in teams more effectively.
If Harry goes to Beauxbatons in fanfiction, his story would take a completely different turn. For starters, he wouldn't be in the middle of the Voldemort situation at Hogwarts directly. But that doesn't mean he'd be safe. Beauxbatons might also face threats, and Harry could be in the center of it in a different way. He might learn different defensive magic techniques which could change how he faces his enemies later. Moreover, his social circle would expand to include students from different countries, which could influence his character development.