The plot might involve a misunderstanding. Let's say a villain frames the Kamen Rider for a crime in the Naruto village. Naruto, believing the false evidence, banishes the Kamen Rider. As the story unfolds, the real villain continues to cause trouble, and Naruto starts to suspect that he made a mistake. Meanwhile, the Kamen Rider is out in the world, trying to find evidence to clear his name and return to help Naruto fight the real threat.
One possible plot could be that in a world where Naruto and Kamen Rider exist together, Naruto, for some reason, sees the Kamen Rider as a threat to his village's safety. Maybe the Kamen Rider's powers are misconstrued as dark magic. So Naruto, in his role as Hokage or a high - ranking shinobi, banishes the Kamen Rider. This could lead to the Kamen Rider having to prove his innocence and find a way back to the village to clear his name.
The shinobi in Naruto's village would likely be divided. Some would support Naruto's decision wholeheartedly, believing that any unknown power like the Kamen Rider's is dangerous. Others might be more skeptical, especially those who are more open - minded or have interacted with the Kamen Rider. As for the Kamen Rider himself, he would probably be angry and confused at first, but then determined to prove his worth and return.
One possible plot could be that Naruto somehow gets transported to the Kamen Rider universe. He might initially be seen as a threat due to his powerful ninja skills. The Kamen Riders could try to stop him, thinking he's a new kind of monster. But as the story progresses, they realize he's not evil and they team up to fight a common enemy that threatens both their worlds.
Well, it could be about a character from Kamen Rider Kiva getting transported to the Naruto universe. Maybe the Kiva character has to learn chakra control and ninjutsu while also trying to find a way back to his own world. He could team up with Naruto and his friends to fight common enemies like the Akatsuki who might be interested in the Kiva powers.
A plot could involve a Kamen Rider who has the ability to use chakra like in the Naruto world. He meets Naruto and they exchange their skills. The Kamen Rider teaches Naruto about his technology and fighting style, while Naruto teaches the Kamen Rider about ninjutsu. Then they have to face a powerful villain who is after the unique combination of their powers.
Well, it could be about a kamen rider who enrolls in the highschool from DxD. Maybe he has to use his kamen rider powers to fight off devils or other supernatural threats that target the school. He could also form an unlikely alliance with some of the characters from DxD, like Issei and his friends.
One common theme is the power exchange. For example, a Kamen Rider might teach Naruto or other ninja about their technology - based powers, and in return, the ninja teach the Kamen Rider about chakra and ninjutsu. It's interesting to see how they combine these different power systems.
One possible plot could be that the Kamen Riders and Power Rangers are forced to team up when a new super - powerful villain emerges that neither group can defeat alone. The Rangers' high - tech weaponry and teamwork combined with the Kamen Riders' unique abilities and forms would make for an epic battle against the foe.
Well, perhaps the fanfic could revolve around Kickhopper finding himself in an alternate universe where the rules of being a Kamen Rider are different. He has to adapt and form a crossover alliance with a local hero. They start by comparing their transformation devices and learn from each other's fighting styles to defeat a group of interdimensional thieves who are stealing important artifacts from both universes.
Well, it could be a plot where Naruto, for some reason, banishes the RWBY characters to another dimension. Maybe he sees them as a threat to his world. For example, their unique abilities might disrupt the balance in the Naruto universe.
In this type of fanfiction, the plot might involve Naruto being exiled due to the council's fear of his growing power. They may see him as a threat to the established order in the village. Naruto, being banished, could then go on a journey to become even stronger outside the village, perhaps finding new allies and learning unique jutsu.