If Naruto and Hinata went back in time in fanfiction, one possibility is that they could change the course of many events. For example, Naruto might be able to prevent some of the tragedies that occurred in his childhood. Hinata could also use her knowledge to help her clan earlier. They might also have the chance to influence the relationships between different characters in a positive way, like improving the relations between the Uchiha and the village.
Well, one possibility is that they could completely rewrite the history of the ninja clans. Naruto, with his positive influence, might be able to make the Uchiha clan feel more accepted in the Leaf Village, preventing the Uchiha massacre. Obito, having seen the destruction his actions caused in the future, could help Naruto in these efforts. Also, they could work together to train younger versions of themselves and their friends to be even stronger, which would have a huge impact on future battles.
In a time - travel fanfiction like this, they could also have the opportunity to meet long - lost characters or discover secrets that were lost in time. Naruto and Shikamaru could learn about the origin of some of the powerful jutsus in their world. And perhaps they could use their knowledge of future technology or ninja tools to create something revolutionary in the past. This could potentially change the balance of power among the ninja villages. However, they would also have to be careful not to be discovered as time - travelers, as that could lead to all sorts of complications.
Well, they could change a lot of things. Maybe Naruto would prevent some of the tragedies that happened in the past. He could stop the Nine - Tails attack on the village, which would completely change his own life and the lives of many in Konoha.
Well, they could also change their own relationships. Maybe Naruto wouldn't be so alone as a child, and Ino could become a stronger ninja earlier. They might train together in ways they didn't before, using the knowledge of future jutsu and strategies. They could also influence the relationships between different ninja clans, like improving the relations between the Uzumaki and the Yamanaka clans.
It could be the same antagonists as in the original Naruto series at first, like the Akatsuki. But if Naruto and Ino change things, new antagonists might emerge. Maybe some ninja who were once allies turn against them because they fear the changes Naruto and Ino are making to the ninja world order.
Naruto's powers, especially his Nine - Tails chakra, could have a huge impact. He could use it to fend off stronger enemies much earlier. Hinata's Byakugan would give her an edge in predicting enemy moves. They could use their powers together to change battles that were originally lost. For example, Naruto could use his Rasengan more effectively with Hinata's support and knowledge from the future.
It could be some new group that emerged due to the changes in the ninja world over time. They might oppose the way Naruto and Hinata's village is being run and want to impose their own ideals.
In this fanfiction, they might see a more advanced Hidden Leaf Village. Maybe there are new jutsus and technologies. For example, the village could be protected by some high - tech barriers instead of just the traditional ninja guards.
Well, if Naruto and Hinata go to the past in fanfiction, it could be really interesting. They could meet their younger selves. Naruto might see his lonely childhood self and try to give him some hope. Hinata could also see her shy younger self and perhaps encourage her to be more confident earlier. And they could also influence the relationships between other characters. For instance, they might help their friends' parents get together or something like that.