Well, when it comes to Naruto time travel and Rinnegan in fanfics, it's often about exploring new storylines. Maybe Naruto himself gets the Rinnegan and travels back in time to train his younger self. This would make him a much more powerful ninja at an earlier stage and could completely change the power balance in the Hidden Leaf Village and among the other ninja villages as well.
In fanfiction about Naruto's time travel and the Rinnegan, one of the coolest concepts could be that a villain with the Rinnegan travels back to the time of the Sage of Six Paths. This could disrupt the entire origin of ninjutsu and chakra. It would be a wild ride as the villain might try to rewrite history to make himself the most powerful being ever. They could influence the Sage to create a different kind of chakra system or even prevent the division of the Sage's power among his sons, which would have a huge impact on the future world of Naruto.
The Rinnegan can be used in time travel fanfiction in Naruto in various ways. It could be used to open portals to different time periods, kind of like how it can create spatial portals in the original series. For example, a character might use the Rinnegan to travel back to the era of the First Hokage to gain knowledge or power.
There's also 'Naruto's Time - Traveling Rinnegan Adventure'. This fanfiction focuses on Naruto exploring different time periods with his Rinnegan ability. He meets his predecessors and learns a great deal about the origin of the ninja arts. It's a great read for those who love to see Naruto in a more introspective and knowledge - seeking role as he travels through time.
The Rinnegan's time travel can completely change character relationships. For example, if a character travels back in time, they might meet their friends or enemies at a different stage of their lives. In a harem fanfiction, this could mean that a male character meets a female character before she has certain prejudices or before she has fallen in love with someone else. So, the time travel allows for a fresh start in the relationship.
In 'Long Rinnegan Naruto Time Travel Fanfiction', a common plot is Naruto being sent back in time accidentally due to some malfunction of his Rinnegan power. Once in the past, he has to figure out how to get back while also trying to use his knowledge and power to make the world a better place. He might team up with younger versions of the legendary sannin or try to change the fate of some of the minor characters. It's always fascinating to read about how the time - traveling Naruto disrupts the normal flow of the Naruto world.
Well, in this fanfiction scenario, perhaps Naruto's Rinnegan gives him unique abilities during the time travel. He and Anko could team up to take on threats that were previously unbeatable. They might also discover secrets about the origin of the Rinnegan or other powerful jutsus that were lost in time. It could be a story of self - discovery for both of them as they navigate a different era.
Kaguya Otsutsuki could also be a main villain. If Naruto travels to a different time period, he might accidentally release Kaguya or she could sense his Rinnegan power from afar and see him as a threat. She could then try to stop Naruto from changing the future or past in a way that would prevent her from being resurrected or stop her plans.
One interesting plot could be Naruto using his time - travel ability with the Rinnegan to go back and prevent the Uchiha massacre. This would completely change the course of the Naruto world. He could try to reason with Itachi and the elders, and maybe find a way to end the conflict without all that bloodshed.
One possibility is that Naruto with his Rinnegan powers could disrupt the power balance in the Sannin era. His modern jutsu and knowledge might give him an edge. For example, he could use his Rasengan in ways that the shinobi of that time have never seen. He might also form unexpected alliances, like befriending Orochimaru before he goes bad, which could change the entire future of the Naruto world.
In certain fanfictions, the use of Rinnegan - powered time travel could lead to the discovery of hidden secrets in the Naruto world. As for the harem, the main character might find himself in situations where he has to protect multiple female characters during his time - traveling adventures. This protection and shared experiences could then lead to the formation of the harem. For instance, he travels to a time when the Akatsuki is more active and saves some female ninjas from their attacks, and they fall for him.
If Naruto had the Rinnegan and could time travel, one possible way the story could unfold is that he might go back to prevent some of the great tragedies in the Naruto world. For example, he could stop the Uchiha massacre. With the power of the Rinnegan, he would be able to anticipate and counteract the actions of Itachi and Danzo. He could also use his time - traveling ability to gain more knowledge about the origin of the ninja world and the secrets of chakra, which could make him even more powerful and better equipped to protect his village and friends.