Well, in such a fanfic, Naruto might gain some extremely powerful and unique abilities. Kaguya being his trainer could mean he'd learn ancient and forbidden jutsus. Maybe he'd also gain a deeper understanding of the chakra and the origin of the ninja world.
In the 'Naruto trained by Kaguya fanfic', Naruto could potentially have a huge power boost. Kaguya is an extremely powerful entity. So Naruto might learn to control his chakra in ways he never thought possible. He could also learn new combat strategies and become more proficient in taijutsu, ninjutsu, and genjutsu under her guidance.
Well, Naruto would likely gain some really unique and powerful abilities. Since Kaguya is extremely powerful, she could teach Naruto some ancient and secret techniques that are not known in the normal ninja world. Maybe he'd learn more about the origin of chakra and how to manipulate it in ways he never thought possible.
In this fanfiction scenario, Naruto and Hinata would likely gain extraordinary powers. Kaguya has immense and unique abilities. Naruto might learn new forms of chakra control or even some ancient jutsu that Kaguya knew. Hinata could improve her Byakugan skills to a whole new level, perhaps even being able to see things on a different plane of existence. They might also gain a deeper understanding of the origin of chakra and the history of the ninja world from Kaguya directly.
If Kaguya is sealed in Naruto in a fanfic, Naruto could potentially use Kaguya's power for good. He might be able to access new jutsu or abilities that were previously unknown. However, there would also be risks. The power could be corrupting, like it was for Madara when he got some of Kaguya's power. Naruto would have to rely on his strong will and the support of his friends to keep from being consumed by it. He could also try to study Kaguya's power to find a way to break the cycle of hatred that has been plaguing the ninja world for so long.
If Naruto absorbs Kaguya in a fanfic, it might lead to a very different storyline. He could use Kaguya's power to bring about a new era of peace more quickly. For example, he might be able to use her power to stop all forms of aggression instantly. Also, his appearance might change slightly, taking on some of Kaguya's physical traits. And his understanding of the chakra and the world's origin could be greatly enhanced.
Well, Naruto might become extremely powerful in terms of his mental manipulation skills. Aizen is known for his cunning and ability to deceive. Naruto could learn new ways to outwit his opponents. He might also gain some unique combat techniques that are more psychological in nature, rather than just relying on his physical strength and ninjutsu.
If Naruto were trained by Toriko in a fanfic, it would be an interesting blend of two different worlds. Toriko's training might introduce Naruto to a whole new concept of the 'food chain' in terms of power. Naruto could learn how to incorporate the energy from different foods into his jutsu. Moreover, the cultural differences between the ninja world and Toriko's world would create some really fun and unique interactions. Naruto might be shocked at first by Toriko's appetite but then learn to respect and utilize the power that comes with it for his own growth as a ninja.
Well, Naruto might gain some really cool new combat skills. Vergil is a very skilled fighter, so he could teach Naruto some advanced sword techniques or unique ways of using chakra in combat. Maybe Naruto would also pick up on Vergil's more strategic and calculating approach to battles.
In such a fanfic, Naruto might gain unique abilities. Cell is a powerful and complex character from Dragon Ball. If he trained Naruto, Naruto could potentially learn new combat techniques, perhaps even something related to Cell's perfect form's regeneration ability. This would make Naruto an even more formidable ninja in the Naruto universe.
Well, in a fanfic where Naruto is trained by Tremor, Naruto could end up with a whole new set of jutsu. Tremor's influence might lead Naruto to combine his existing Rasengan technique with earth - based chakra manipulation. This could result in a Rasengan that not only has the spinning force but also causes massive tremors upon impact, making it a much more devastating attack. Also, Naruto might learn to sense opponents' movements through the vibrations in the ground, giving him an edge in combat.
If Naruto were trained by Whis in a fanfic, it could lead to some really interesting crossovers. Naruto's ninja skills combined with Whis' training could make him a force to be reckoned with. He might even develop some new forms or abilities that are a blend of the Naruto and Dragon Ball universes. For example, he could use his chakra in ways similar to how the Dragon Ball characters use ki, but with his own ninja - style twist.