In a world where Naruto is a fish out of water, the local bullies or those who uphold the unfair traditions of the world could be the antagonists. They might oppose Naruto when he tries to change things for the better.
One idea could be that Naruto arrives in a world full of magic. He tries to understand and master the new magic system using his ninja skills as a base. For example, he might find that his chakra control can be adapted to control magical energy in a unique way.
Gohan's adaptation in the Naruto world in this fanfic would be a complex process. He would be faced with a world full of new rules, new powers, and new people. At first, he'd be confused, but his intelligence would help him. He'd study chakra, the most fundamental part of the Naruto world. He might also be intrigued by the different jutsu and try to incorporate some of the principles into his own fighting style. Socially, he'd have to learn the ways of the ninja, like their loyalty to their villages. Over time, he could become an important part of the Naruto world, using his Saiyan abilities in new and unique ways that blend with the ninja way.
In a fanfic where Gohan goes to the Naruto world, his presence would disrupt the balance. His Saiyan strength is on a different level compared to most Naruto characters. He might start by being confused about the ninja way and all the different clans. However, he could also introduce new concepts from his world. For example, his training methods. And he would probably make some really strange friends. Some ninjas might be in awe of his power, while others might be a bit scared. He could also end up having some really interesting battles against the strongest ninjas, like Naruto or Sasuke, which would be a clash of two very different power systems.
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, Naruto would probably be really confused at first. The world of Kim Possible is quite different from his own. He might try to use his ninja skills to help Kim with her missions. Maybe he'd show off his Rasengan to Ron and Rufus, and they'd be super impressed. He could also learn a thing or two about modern technology in that world.
It could be about Naruto's adventures in a Western - style setting. Maybe he uses his ninja skills in a world similar to the Wild West, facing new enemies and challenges.
Naruto could also interact with Weiss. There might be some initial clashes due to their different personalities. Weiss is more refined and Naruto is more brash. But over time, they could come to respect each other's strengths. He might also teach her some ninja stealth techniques.
Naruto might meet some young and talented Kumo ninjas. They could be eager to test their skills against Naruto or learn from him. Maybe there are some unique characters like a Kumo ninja with a special bloodline limit that Naruto has never seen before.