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.
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.
One idea could be an OC who has a unique power to communicate with Titans on a deeper level. This power could be a double - edged sword, as it might draw unwanted attention from both humans and Titans. Another plot could revolve around an OC who is a master of stealth and uses it to uncover secrets within the Walls. For example, they could discover hidden chambers or forgotten knowledge about the Titans.
One interesting plot could be Naruto, now in Obito's body, trying to prevent the Uchiha massacre. He could use his knowledge from his past life to change the course of events and save his friends in the Uchiha clan. Another idea might be Naruto exploring Obito's relationship with Rin in a new way, bringing his own sense of loyalty and friendship to the dynamic.
A really interesting plot could be that Tobirama is reborn as a non - ninja, but still has his chakra control abilities. He has to find a way to use his skills secretly while living a normal life at first. As he discovers more about the world he's in, he starts to influence the ninja world from the outside, creating a whole new dynamic in the story.
One interesting plot could be Naruto using his ninja skills in the world of Tsuna. For example, he might use his shadow clone jutsu to help Tsuna deal with multiple threats at once. Another could be Naruto teaching Tsuna some of his unique chakra control techniques which could enhance Tsuna's own combat abilities in his world.
Another plot could be that Nagato is reborn with new powers. With these powers, he aims to unite the different ninja villages in a more peaceful way than before. He could start by building alliances through diplomatic means and by using his powers to solve common problems, like natural disasters or threats from outside the ninja world.