There could be a focus on Naruto learning new forms of the Rasengan. Hokage Naruto, with his vast experience, could teach Naruto different ways to infuse the Rasengan with other elements more easily. Maybe Naruto would learn how to quickly switch between a Fire - Rasengan and a Wind - Rasengan during combat.
Perhaps in this fanfiction, Hokage Naruto takes Naruto on a journey to different hidden villages to train with their unique masters. They could visit the Sand Village and learn from Gaara about controlling sand and how to use it in combination with Naruto's own abilities. This would not only expand Naruto's skill set but also strengthen the bonds between the villages.
In some fanfictions, the Hokage trains Naruto in the art of sealing techniques. Since Naruto has the Nine - Tails, learning about sealing could be crucial for him to better manage its power or even use it in new ways. For instance, the Hokage could teach Naruto how to create seals that can store and release chakra in a more efficient way. Another aspect could be the Hokage training Naruto in espionage. Naruto would learn how to gather information secretly, which is an important skill for a ninja. This could involve disguises, infiltration techniques, and how to read body language to detect lies.
One possible thing that could happen is that Naruto could teach his younger self some advanced jutsu. For example, he might show the younger Naruto how to better control the Nine - Tails' chakra earlier. This would give the younger Naruto a significant power boost and change the way he approaches battles in his early days.
Well, it could be that Naruto meets the Hokage in a different time - space. They might work together to change some important events in the history of the village. For example, preventing a great disaster or changing the fate of some important characters. And Naruto could learn a great deal from the Hokage's wisdom and leadership in this encounter.
One of the most popular Hokages in these fanfictions is the Fourth Hokage, Minato Namikaze. Since he is Naruto's father, there's a natural connection. Minato can train Naruto in his unique space - time ninjutsu and share his experiences as a Hokage. Another is the Third Hokage, Hiruzen Sarutobi. He has a wealth of knowledge and can teach Naruto about the history and traditions of the village. Also, the Sixth Hokage, Kakashi Hatake, is often featured. Kakashi can train Naruto in his own combat style and also in how to handle the responsibilities of being a leader.
Sasuke could be an alternative. He has strong ninja skills and a deep understanding of the ninja world. His experiences have made him grow into a very capable person, and his Sharingan gives him an edge in combat and strategic planning.
It could also be a very emotional encounter. Young Naruto might be in awe of seeing his future self as Hokage. Hokage Naruto could tell young Naruto about all the people who believed in him, like Iruka - sensei and Kakashi - sensei. This would make young Naruto realize the importance of the relationships he has and the impact they have on his future.
Maybe Naruto trains Sakura in combat. He could teach her some of his unorthodox fighting moves. Since Naruto has faced so many different opponents, he has a wide range of combat experience. He might show Sakura how to better anticipate an opponent's moves and counter them effectively. Sakura, in turn, could use her intelligence to analyze and improve on the techniques Naruto teaches her.
In the fanfiction, they could face a common enemy. Naruto, with his powerful ninjutsu and Shikamaru, with his clever strategies, would have to work together. For example, they might be up against a group of rogue ninjas. Naruto could be the main force in direct combat, while Shikamaru uses his shadow jutsu to immobilize the enemies at crucial moments, and during their training, they prepare for such scenarios.
Perhaps the fanfiction could be about Naruto training Percy in stealth. Percy, being a demigod, often charges into battle head - on. Naruto, on the other hand, is a master of stealth. He could teach Percy how to move quietly and undetected. This would be a great advantage for Percy when he has to infiltrate a monster's lair or spy on the enemy. The story could show Percy struggling at first but gradually getting better with Naruto's guidance.
Perhaps Naruto feels that the Hokage has been too strict or unfair in dealing with certain situations. Like if the Hokage didn't support Naruto's way of trying to bring peace and unity, which Naruto firmly believes in. This could lead to a growing resentment and eventually hatred.