If Naruto becomes a Kishin in fanfiction, he would likely lose his positive values. He might start to crave power in a more sinister way. His relationships with his friends would be severely strained as they would not recognize the new, dark Naruto. His once - cherished village would probably view him as a threat.
Well, if Naruto becomes the Kyuubi in the fanfiction, he would likely have an overwhelming amount of power. He might be able to defeat his enemies with ease. But he would also face the struggle of controlling such a powerful and wild force inside him. Maybe his friends would be both in awe and a bit scared of him at first.
Well, if Naruto becomes Mikoto, he would be a female in the body of Mikoto. He could bring his own values and experiences as Naruto. This could potentially change the relationship dynamics within the Uchiha clan. He may try to bridge the gap between the Uchiha and the rest of the village in a way that Mikoto might not have been able to do in the original story due to her own limitations and the circumstances of the time.
In this kind of fanfiction, Naruto might gain even more incredible power. He could have enhanced physical abilities like super strength and speed, as well as new jutsu related to the bijuu's nature. For example, if he becomes the Nine - Tails bijuu, he might be able to use the Tailed Beast Ball more effectively and on a larger scale. His appearance might also change, perhaps taking on some of the characteristics of the bijuu, like fox - like features if it's the Nine - Tails. This could lead to new relationships and dynamics with other characters. His friends might be in awe of his new power, while his enemies would be even more fearful.
Well, if Naruto becomes the reaper in fanfiction, he would probably have a whole new set of powers. He could start reaping souls in the Naruto universe, which would be a huge change. Maybe he'd use his new reaper abilities to deal with the more dangerous enemies in a different way, like sending their souls to some sort of afterlife realm.
If Naruto becomes a Digimon fanfiction, it could be really interesting. Naruto might find himself in the digital world, trying to adapt his ninja skills to deal with Digimon. He could form an unexpected bond with a Digimon partner, like how he did with his friends in the Naruto world. And his sense of justice would surely lead him to fight against any evil Digimon that threaten the digital world.
In some fanfictions, if Naruto becomes the Kyuubi, he might gain ultimate power. He could have the Kyuubi's full strength and abilities, like its massive chakra reserves. This could make him nearly invincible in battles. He might also change in appearance, perhaps having some Kyuubi - like features. For example, his eyes could turn red like the Kyuubi's, and he may grow claws or fangs. His personality could also be affected, becoming more ferocious and wild at times, but still having Naruto's underlying kindness.
Well, he could start judging the souls in the Naruto universe. Maybe he'd use his new powers to clean up all the evil ninjas in a very final way.
If Naruto becomes the Flash in fanfiction, he would be incredibly fast. He could use his new speed to outmaneuver his enemies in combat. For example, in battles against the Akatsuki, he could zip around and strike them before they even realize it. His Rasengan might also be enhanced as he could deliver it with the speed of the Flash, making it even more powerful and difficult to dodge.
Well, in such a fanfiction where Naruto becomes evil, it would be a total upheaval of the Naruto universe we know. His dark side could lead to alliances with villains like Orochimaru. He might start to hunt down those he once considered friends. His change could also be a result of some great betrayal, and his quest for vengeance would make him a very dangerous force. This would not only change the story's dynamic but also the fates of all the characters involved.
Well, he'd probably be super OP. He already has his ninja skills and if he gets the Avatar powers on top of that, he could be nearly unbeatable. He might use the Avatar state to enhance his Rasengan or something.