Well, he might find himself in a world with completely different chakra rules. Maybe in this new world, his ninja skills are either overpowered or nearly useless. He could meet new characters that are similar to his friends in Konoha but with different personalities. For example, he might find a version of Sasuke who is more friendly from the start.
He could end up in a world full of magic instead of chakra. Naruto would then have to learn how to adapt. He might try to use his shadow clone jutsu in this magic - based world and find that it has unexpected effects. Also, he could be seen as a strange being since he has no knowledge of the local magic system at first.
He may find that his ninja skills are either very useful or completely ineffective in the new world. If the new world has a different form of combat, Naruto would have to adapt quickly. Also, he could encounter new forms of nature energy or magic that he has to learn to control. There might be a love interest for Naruto in this new world as well, which could add a whole new layer of complexity to the story.
Naruto would probably be really confused at first in the Pokemon world. But then he'd start to explore. He might mistake a Pokeball for some kind of ninja tool at first. However, once he figures out how things work, he could become a really strong Pokemon trainer. His determination, which is one of his main traits in his own story, would help him a great deal in this new world. He would not give up easily when it comes to training his Pokemon or facing tough opponents in Pokemon battles.
Well, Naruto might be really surprised at first. He could find that the fighting styles are different as they are designed by females. Maybe he would have to adapt to new social rules and ways of communication. For example, he might need to be more polite in a different way than he is used to in his own world.
In the fanfic, Goku could become friends with Naruto easily. Since they both have a strong sense of justice and a will to protect their friends. Goku might teach Naruto some of his training methods, like training under heavy gravity. And Naruto could show Goku the unique aspects of ninja villages and how they function.
Well, he might make new friends who have different magical abilities or come from different backgrounds. Maybe he'll learn new spells or magical theories not taught at Hogwarts.
In this kind of fanfiction, Harry might encounter new magical creatures that don't exist in his own dimension. For example, he could meet some kind of shape - shifting beasts that can change into any form they like.
He might face unique challenges. Hozukijou could have its own set of rules and obstacles that Naruto has to figure out, like perhaps different types of jutsu or magic that are specific to that place.
Well, Naruto might face a lot of challenges in Iwa. He could encounter new types of jutsu that are unique to Iwa ninjas. Maybe he'll make some new friends or foes there.
In this fanfiction, Naruto might face new challenges in Suna. He could encounter different shinobi with unique fighting styles. Maybe he'll form new alliances or have some interesting cultural exchanges.
Well, he might encounter new and powerful ninjas. In Kiri, there are strong water - style ninjas. Naruto could learn new techniques or gain new allies. Maybe he'd get into some battles and show off his Rasengan to the Kirigakure folks.