A possible plot for 'oc reborn as naruto fanfiction' is that the OC, now in Naruto's body, decides to focus on uniting the ninja clans in a different way. They use their modern - like thinking (from their previous life) to break down the barriers between the clans. They might also use their knowledge of future events to prepare the village better for upcoming threats, like the Akatsuki. They could start by sharing information with the elders in a more diplomatic way, which would be a big change from Naruto's impulsive nature in the original story.
One idea could be that the OC, reborn as Naruto, uses their prior knowledge to quickly master jutsu. For example, they might know about the Rasengan from the start and be able to perfect it faster. Another plot could involve the OC changing the relationships in the village. Maybe they befriend Sasuke earlier and prevent his defection. Or they could introduce new ninja techniques from their past life to the Hidden Leaf.
Another plot could involve an OC reborn into the body of a criminal in the Naruto world. They have to struggle to redeem themselves and prove that they are not the same person as the original criminal. Along the way, they could discover the real reasons behind the original criminal's actions and try to right the wrongs that were committed.
Well, perhaps the OC reborn as Kurama tries to find a way to coexist peacefully with the jinchuriki in a different way than in the original story. They could use their unique perspective to broker better relationships between the tailed beasts and the humans. Maybe they also try to uncover secrets about the origin of the tailed beasts that were previously unknown.
One idea could be an OC who has a special power related to time manipulation in the 'hitman reborn' universe. They could use this power to change the outcome of battles or prevent certain tragedies. Another could be an OC that is a long - lost relative of one of the main characters and has a different view on the mafia world, causing some internal conflicts.
One idea could be that the reborn OC genius uses their extraordinary intelligence to solve a mystery that has baffled the entire community. For example, they might figure out the secrets behind an ancient artifact's power.
One idea could be that the OC, now as Kakashi, has to deal with the same traumas Kakashi had but with a different perspective from their original self. For example, they might handle the loss of their comrades in a new way that changes the course of events in the Naruto world.
An interesting approach for a 'Naruto Reborn OC Fanfic' would be to create an OC who is an outsider to the ninja world but has to adapt quickly. This OC could be from a far - off land where they have different fighting styles or powers. For instance, a place where they use music as a form of combat, and when they come to the Naruto world, they have to blend in while also introducing their unique skills. They could form unexpected alliances and face challenges that are different from what the native ninja are used to.
One idea could be to give the OC a new power or ability in their reborn state. For example, if it's a fantasy setting, they could gain the power to control an element they were previously weak against. Another idea is to change their personality slightly due to their rebirth experience, like becoming more confident or cautious. You could also explore a different backstory for the OC in the fanfiction, perhaps one that was hidden before their rebirth.
The OC could be a descendant of a powerful clan that was thought to be extinct. Their presence in the Naruto world stirs up interest among many characters. The OC's knowledge of ancient jutsu and their kind heart draw in characters like Kakashi, Shikamaru, etc. into a harem. The OC then has to navigate the complex relationships while also trying to keep their clan's secrets safe.
One idea could be that the OC team is on a mission to retrieve a rare and powerful ninja artifact that has been lost for centuries. This could lead to battles with other ninja clans who also want the artifact.
One idea could be an OC who is a time - traveler from the future. They come back to the Naruto world to prevent a great disaster that they know will occur in the future. This OC could have unique powers related to time manipulation or future - sight.