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.
For an 'oc reborn fanfiction', you might consider having the OC reborn with memories of their past life intact. This could create a lot of internal conflict as they try to figure out how to use this knowledge. Maybe they remember a great wrong that was done to them or someone else, and they are now reborn to set things right. Also, the rebirth could be a chance for the OC to form new relationships. They could meet characters from their past life in new ways and develop different dynamics with them.
Well, you could have the OC reborn into a different time period. Say, if the original story was set in a medieval era, the OC could be reborn in a modern or futuristic world. This would lead to a lot of interesting situations where they have to adapt. Or, make the OC reborn as a different species. If they were human before, they could be reborn as an elf or a magical creature, which would open up new plotlines regarding their new form and how they interact with others.
Maybe the OC reborn as Sasuke has some special powers from their previous life that they combine with Sasuke's natural abilities. This could lead to new and exciting jutsu creations. They could also use their knowledge of future events to help Sasuke form better relationships with his teammates, like Naruto and Sakura, which would in turn affect the overall story arc of Naruto.
Also, the oc might have different goals than Issei. While Issei is often focused on his perverted desires as well as becoming stronger to protect his friends, the oc could have a more noble or self - centered goal like finding a way back to their original world or using the power in this new world for personal gain in a non - perverted way. This contrast in motives can create a lot of tension and interesting plot developments.
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.
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.
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.
A possible plot is that the reborn female OC starts to form a different kind of relationship with the existing characters. Since she's female, her friendship with Annabeth could be more of a sisterly bond where they support each other in different ways compared to Percy and Annabeth's relationship. And she might have a romantic sub - plot with a new character, someone who was not really in the spotlight in the original series. This new relationship could be shaped by her unique identity as a reborn character.
One idea could be that the female OC is reborn as a powerful witch in the Vampire Diaries world. She could use her newfound powers to protect the Mystic Falls gang from new threats. Maybe she discovers a hidden prophecy that involves her and has to figure out how to fulfill it while dealing with the complex relationships between vampires, werewolves and witches already in the story.