Sasuke's reaction could be complex. At first, he would be enraged. After all, the Rinnegan is a symbol of his power and his journey to gain strength. However, he might also have some mixed feelings. He and Naruto have a deep bond, and he might wonder if Naruto had a good reason for taking it. But overall, his initial reaction would likely be one of fury and a desire to get his power back.
Their relationship would likely become more complex. With the Rinnegan involved, they might have to rely on each other more for understanding its powers. They could become more protective of each other, knowing the power and the danger it brings.
Well, it could lead to a major shift in the power balance among the characters. Sasuke would be weakened without his Rinnegan, and Naruto would have to deal with the new power. There might also be some internal conflict within Naruto as he tries to come to terms with using Sasuke's power. Maybe he would feel guilty at first, but then realize it's for the greater good. Also, other characters like Kakashi or Sakura might have different reactions. Kakashi could be worried about Naruto being corrupted by the power, while Sakura might be more concerned about Sasuke's well - being without his most powerful ability.
If it's a crossover with the Fairy Tail guild, Natsu would be an interesting character to pair with Sasuke. Natsu is hot - headed and Sasuke is brooding. Their personalities contrast but they are both extremely powerful. Sasuke's Rinnegan powers could be used in combination with Natsu's fire - based magic in battles against powerful enemies. And they could have some great banter as they try to understand each other's worlds.
One idea could be a story where Sasuke, with his Sharingan, discovers a new power related to the Rinnegan that was hidden within Naruto all along. Maybe Naruto has some dormant Sage of Six Paths energy that when combined with Sasuke's powers, they can unlock a new level of strength to fight a powerful, unknown enemy.
In the manga, Sasuke doesn't regain his Rinnegan. The story progresses without this particular change. The power he had before is maintained without reverting or regaining additional abilities related to the Rinnegan.
The plot might involve Naruto with the Rinnegan being a bit of an outcast in the village at first because of the strange and powerful new dojutsu. Fem Sasuke could be the one to understand him and encourage him to embrace it. They could then go on a quest to discover the origins of the Rinnegan together, facing various challenges along the way, like ancient ninja traps and powerful, long - forgotten clans.
Naruto would be an interesting character to pair with Sasuke. Their long - standing relationship and the contrast between Naruto's positive energy and Sasuke's more brooding nature could create great drama in a crossover situation. Especially when Sasuke has the Rinnegan, Naruto might have to adjust his way of fighting and interacting with him.
Well, for Sasuke's Rinnegan to be involved in time travel in fanfiction, it might be linked to some ancient jutsu or hidden knowledge. For example, there could be a long - forgotten scroll that details how to use the Rinnegan for time - related feats. Sasuke, being the inquisitive and powerful ninja he is, could stumble upon this knowledge. Then, he might have to face the consequences of meddling with time, such as changing the course of events in the Naruto universe.