Maybe Sakura's one - eyed Sharingan is the result of an experiment gone wrong. She has to struggle with controlling its power while also dealing with the fact that others are after her for this unique ability. She could go on a journey to find a way to reverse the experiment or at least master the power for good. For example, she might meet a wise old ninja who gives her some clues on how to control it.
In a fanfiction, Sakura's one - eyed Sharingan could give her the ability to predict the future. However, every time she uses it, it drains her of a significant amount of chakra. She has to decide when and how to use this power. She might use it to prevent a major war from happening, but in doing so, she puts herself in great danger as she is left vulnerable after using the power.
One plot idea could be that Sakura, with her one - eyed Sharingan, discovers a hidden power within it that allows her to see into alternate dimensions. She then uses this power to find a way to save her comrades from a powerful enemy that has them trapped in a different realm.
One plot idea could be that Sakura somehow acquires a Sharingan, perhaps through a scientific experiment gone wrong in the Hidden Leaf Village. She then has to learn to control it while also dealing with the suspicion of her fellow villagers.
To develop Sakura's character, she could be put in situations where she has to rely on her Sharingan - enhanced skills to save her friends. This would force her to grow and become more independent. For instance, if Naruto and Sasuke are captured and she has to use her unique ability to rescue them. She would learn more about her own strength and leadership capabilities. Also, she could have internal conflicts about whether to use the power for revenge or for the greater good, which would further shape her character.
One plot idea could be a character who is an experiment and has only one Sharingan eye implanted. They struggle to control its power and are hunted by those who want to use their unique situation. For example, they might have to constantly fight off rogue ninjas who think they can steal the eye's power.
One plot idea could be a character who was born with only one Sharingan eye and has to struggle to master its powers in a world where most Uchiha have two. They might face discrimination from their clan for being different. Another idea is that a character loses one of their eyes in a battle and then has to adapt to having just one Sharingan, with different abilities emerging as a result of this change. For example, the single Sharingan could have enhanced perception abilities to make up for the lack of a second eye.
One idea could be to cross it with a fantasy world like Middle - earth. The one - eyed owl could be a mysterious creature in that world, perhaps a messenger of an ancient magic. Another idea is to cross it with a superhero universe. The owl could have some unique power that aids the superheroes in their battles, like enhanced vision that can see through illusions.
One idea could be that the character with the Sharingan is banished due to false accusations of using its power for evil. He then has to journey alone, facing challenges and learning to control his power in new ways. Maybe he meets a group of outcasts who he befriends and together they fight against the unjust system that banished him.
One idea could be a character from RWBY obtaining the Sharingan and using its abilities in combat. For example, Ruby could get the Sharingan and combine its precognitive abilities with her own speed, making her an even more formidable fighter.
One idea could be exploring a different origin for the Mangekyou Sharingan. For example, what if it was related to an ancient Uchiha pact with a hidden spirit? Another could be a story where a non - Uchiha character somehow gains the ability to use the Mangekyou Sharingan and has to deal with the consequences. Or perhaps a fanfiction where the Mangekyou Sharingan has additional powers that are not shown in the original Naruto series, like the ability to time - travel.
One idea could be a story where the main character, who has the Eternal Sharingan, has to face a new and powerful enemy that can manipulate time. With the power of the Eternal Sharingan, the character has to find a way to break the enemy's time - based attacks and defenses. Another plot could revolve around a character with the Eternal Sharingan trying to uncover long - lost secrets of the Uchiha clan that are hidden deep within the Sharingan's powers. Maybe there are ancient jutsu or prophecies that only the Eternal Sharingan can unlock.
One idea could be a story where Naruto somehow gains the Golden Sharingan. He could use its unique powers to see through genjutsu more easily and also have enhanced perception in battle. For example, he might be able to predict his opponents' moves better. Another plot could involve Naruto using the Golden Sharingan to unlock a new form of his Rasengan, perhaps one with the ability to disrupt an enemy's chakra flow on a deeper level. Or, it could be a story where Naruto has to team up with a character who has knowledge of the Sharingan to fully understand and control the Golden Sharingan's powers.