Naruto himself could be in jail fanfiction. Maybe he was framed for a crime he didn't commit and has to prove his innocence from within the prison. Sasuke is also a likely candidate. His brooding and sometimes anti - social nature could lead to him getting into trouble with the law in a fanfiction setting. Another one could be Orochimaru. Given his history of unethical experiments, it's not hard to imagine him ending up in jail in a fan - created scenario.
I think Hinata could be in Naruto jail fanfiction in a really unique situation. Maybe she was trying to protect someone and in the process broke some important village laws. It would be interesting to see how her shy nature would handle the prison environment. Shikamaru, with his lazy but intelligent ways, could also end up in jail if he got involved in some political intrigue that backfired on him.
Naruto, Sasuke, and Sakura are the most obvious choices. They are the main characters and their interactions are always interesting. Naruto would bring his energetic and fun - loving nature, Sasuke his brooding intensity, and Sakura her intelligence and strong - willed personality.
Iron Man is another candidate. Tony Stark's technology and Naruto's ninja techniques could be a great contrast. They could learn from each other. Stark might be interested in Naruto's chakra - based powers and try to replicate them in some way, while Naruto could be amazed by Stark's high - tech gadgets.
Definitely Naruto and the Punisher first. Naruto would be intrigued by the Punisher's methods and would try to understand his motives. It's also possible that Sakura could interact with the Punisher. She's a strong - willed character, and she might try to either stop the Punisher if she thinks his actions are too extreme or help him if she sees the good in his goals. And Jiraiya might also be a character who could cross paths with the Punisher. Jiraiya's worldliness and his own sense of right and wrong could lead to some deep discussions between them.
Naruto is a very likely character. Given his rebellious nature and his history of being an outcast in some ways, it's easy to imagine a scenario where he gets caught up in something that lands him in prison. His determination to break free and his loyalty to his friends would make for an interesting story.
Sasuke. He has such a complex character arc and his death would have a huge impact on the story. So, in fanfiction, he's a likely candidate to come back to life and continue his journey. Maybe he has some unfinished business or a new purpose to fulfill.
Obviously Naruto himself is very likely to appear. He is the main character after all. Sasuke would also be a common character as his relationship with Naruto is so central to the story. Then there are the important figures like the Hokages, especially the ones like Minato and Hashirama who had a big impact on Naruto's life. And of course, characters like Kakashi who played a major role in Naruto's growth.
Definitely the Teen Titans. Robin would be interested in Naruto's strategic mind and combat skills. Starfire might be fascinated by Naruto's unique culture. Beast Boy and Naruto could bond over their fun - loving natures. And Cyborg would be intrigued by Naruto's chakra - based abilities compared to his technological ones.
Iruka sensei could also be very helpful. He has always been like a father figure to Naruto. He would support Naruto through this strange transformation, offering advice on how to handle the reactions of others in the village and how to adapt to this new situation without losing sight of his ninja goals.
Naruto himself is very likely to be changed. His journey to become Hokage could take a different path. Maybe he discovers his power in a more unique way or has different mentors along the way. Sasuke is also a prime candidate. His quest for revenge could be altered, perhaps he finds a different way to deal with his family's past without going down the dark path he originally did.
Iruka and Mizuki are also possible characters for role reversal in fanfiction. Iruka could be the one with some hidden, not - so - good motives, while Mizuki could be the kind - hearted teacher figure. This would turn the early Naruto story on its head, as Iruka was Naruto's first positive influence in the original series. The new dynamic between Naruto and these two reversed characters would open up a whole new set of story possibilities.