One interesting storyline could be a young ninja who discovers they have an innate ability to master the Sharingan at an extraordinary rate. They might then face challenges from jealous rivals within their own village who fear their growing power. Another could be a Sharingan master who has lost their sight due to overuse of the Sharingan but discovers a new way to 'see' through chakra perception, leading to a whole new set of adventures.
Well, in some 'naruto of the mangekyou sharingan fanfiction', there might be a plot where a character discovers a hidden power within the Mangekyou Sharingan that was previously unknown. This power could be related to time - like being able to freeze time briefly in a battle. Or perhaps a story where the wielder of the Mangekyou Sharingan has to make a difficult choice between using its power for good or succumbing to the dark temptations that often come with such a powerful ability. It could lead to an internal struggle that shapes the character's journey.
One interesting storyline could be Naruto discovers he has Sharingan after a strange encounter with an ancient Uchiha artifact. This new power makes his enemies question his identity and alliances, and he has to struggle with the newfound power while still being true to his ninja way.
One interesting storyline could be Sakura somehow getting the Sharingan. Maybe she's involved in an experiment gone wrong that gives her the Sharingan's power. This would completely change her abilities and how she interacts with Naruto and the others.
One interesting storyline could be Naruto using the Sharingan to copy the magic of Fairy Tail wizards. He could then combine his ninja skills with the copied magic, creating unique fighting styles. For example, he might copy Erza's requip magic and use it to quickly change his ninja tools during battle.
One interesting storyline could be a character from Kumo who obtains the Sharingan through some mysterious means. Maybe they were part of a secret experiment that combined the powers of different ninja villages. This character then has to struggle with the new power, as it comes with a price, like a constant battle against the dark urges that the Sharingan can bring. They might also face discrimination from their own village who fear their new, unknown power.
One interesting storyline could be the guild master leading the Naruto characters on a new and dangerous mission outside of the main Naruto plot. Maybe they are exploring a mysterious land filled with unknown ninja techniques.
One interesting storyline could be Naruto being trained by a Jedi Master in a world where the Force and chakra co - exist. He might learn to combine his ninja skills with lightsaber combat. For example, using his Shadow Clone Jutsu to create multiple decoys while attacking with a lightsaber. Another could be Naruto using the Force to enhance his Sage Mode, allowing him to sense threats from a greater distance.
In some cases, the 'naruto master of the sharingan fanfiction' could be about Naruto using the Sharingan to uncover secrets about the Uchiha clan that were previously unknown. This could tie into the overarching Naruto story, such as revealing more about the history of the Uchiha massacre or the true nature of the Sharingan's origin. It may also bring new story arcs where Naruto has to deal with ancient threats that were once related to the Uchiha and their powerful eyes.
Well, a plot might be that Naruto is experimented on by Orochimaru. Orochimaru, always interested in powerful abilities, tries to implant the Sharingan into Naruto. Naruto initially struggles with this new power as it's not native to him. But with his strong will, he begins to master it and uses it in ways no Uchiha has before. He could combine the Sharingan's visual prowess with his Rasengan, creating an even more powerful attack. For example, he might be able to see the chakra flow within an enemy more clearly with the Sharingan and then direct his Rasengan to target the weakest points.
A possible plot could be that Naruto is given a temporary Sharingan by an ancient Uchiha spirit. With this Sharingan, he starts to see the world in a different way, and he realizes that there are hidden threats in the ninja world that only the Sharingan can detect. He then embarks on a journey to find out more about these threats and how to stop them. Another plot could be that Naruto meets an Uchiha survivor who teaches him how to use the Sharingan in a way that no one else has thought of. This new way of using the Sharingan could help Naruto in his fight against the Akatsuki. And there could also be a plot where Naruto's Sharingan evolves in a unique way because of his Uzumaki heritage.