One plot idea could be that Naruto, with his Sharingan (assuming some kind of crossover or unique power-up), has to protect Ino from a new and powerful enemy. Maybe an ancient clan has emerged that wants to use Ino's mind - control abilities for their own evil purposes. Naruto, with his Sharingan - enhanced perception and combat skills, stands in their way.
A more adventure - based plot could be that Naruto and Ino go on a quest to find a way to control the Sharingan better. They travel to different hidden villages and encounter various challenges along the way. Ino uses her medical and mind - related skills to help Naruto when the Sharingan starts to have negative effects on him, like overloading his senses or causing him to have visions of a dark future.
Another idea is a love - triangle type of situation where Naruto has the Sharingan and is caught between his feelings for Ino and his loyalty to his village. The Sharingan might give him new insights into his emotions and also attract unwanted attention from other ninja clans who fear his new power. Ino, on the other hand, is trying to figure out if Naruto's feelings for her are real or just a side - effect of his new power.
Perhaps in the fanfiction, Naruto gets the Sharingan in a battle where he absorbs the chakra of an Uchiha enemy. Hinata notices a change in him, not just in his appearance but also in his behavior. She tries to reach out to the old Naruto she knew. As she does, they start to train together and gradually fall in love while exploring the new abilities Naruto has.
Another plot idea is that Naruto, Sakura, and Ino are transported to a different dimension. In this dimension, they have to find a way back home while also dealing with the new and strange rules. They meet different versions of themselves and their friends. This makes them question their identities and relationships. Along the way, they have to combine their powers and wits to overcome the challenges and find their way back to their own world.
A plot could involve a time - travel aspect. Naruto, Ino, and Sakura are sent back in time to their early days at the academy. They use their future knowledge to change some events, and in the process, their relationships develop in different ways. Naruto could see Ino and Sakura in a new light as they all struggle to keep their time - traveling a secret and deal with the changes they're making to the past. This could lead to a complex web of emotions and relationships between the three.
One plot idea could be that Demon Naruto is on a quest to regain his humanity and Ino, with her mind - related abilities, tries to help him. She might be the only one who can reach the part of him that is still Naruto beneath the demon exterior. Another could be that they are forced to team up against a common enemy that is threatening the Hidden Leaf Village. The demon powers of Naruto give them an edge in battle, but they also attract unwanted attention.
Perhaps Naruto discovers a hidden power within himself that only Ino can help him control. In the process of training together, they grow closer. Their relationship could also face challenges from their friends who don't understand their newfound closeness at first.
One idea could be that Dark Naruto, with his edgier and more unpredictable nature, is initially at odds with Ino. But as they are forced to work together on a mission, they gradually start to understand each other. Dark Naruto might see Ino's strength in her mind - jutsu abilities and Ino could start to see the good in Dark Naruto beneath his tough exterior.
Perhaps Naruto's intelligence allows him to discover a new form of jutsu related to the mind, which Ino is naturally interested in. They collaborate to perfect this jutsu, spending long hours together in research and practice. During this time, they start to see each other in a different light. Their friendship evolves into a romantic relationship, and they face challenges from those who oppose their new jutsu's development.
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.