In a crossover with the DC Universe, Naruto could be brought to Gotham City. He initially clashes with Batman due to their different methods of dealing with crime. However, they soon realize that there is a greater threat that requires their combined skills. Naruto's agility and combat skills, along with Batman's detective skills and gadgets, would make for an exciting story as they take on a supervillain.
Maybe in a crossover with the Bleach universe, Naruto as the Seventh Hokage discovers a strange spiritual energy leak that is affecting both the Soul Society and the ninja villages. He teams up with Ichigo to find the source of the leak and stop it. Along the way, they compare their powers and learn from each other.
A crossover with the Harry Potter world would be interesting. Naruto, as the Seventh Hokage, could visit Hogwarts. He might be confused by the magic there at first, but then start to find similarities between chakra and magic. He could even team up with Harry Potter to fight against a common enemy that threatens both the wizarding world and the ninja world.
If Naruto changes something major in the past, it could disrupt the timeline. For example, if he prevents the Uchiha massacre, Sasuke's path would be completely different. He might not have the same drive for revenge, which could mean he doesn't leave Konoha. This would change Naruto's own growth as a ninja, as Sasuke was a big part of his motivation to get stronger.
Maybe there's a threat from a long - forgotten enemy. Naruto, as Hokage, has to mobilize the village's forces, including Sasuke in the Anbu. Sasuke discovers some old secrets related to this enemy that could change the course of the battle. They then have to race against time to use this knowledge to their advantage. This could involve Sasuke going on solo missions within enemy territory while Naruto holds the fort at home and plans the overall strategy.
One aspect that could be explored in Naruto Seventh Hokage cross - fanfiction is his leadership skills in new and unexpected situations. For example, he might be thrown into a parallel universe where the ninja world has different rules and he has to adapt his leadership style accordingly. Maybe in this universe, the villages are not as united as in his own, and he has to find ways to bring them together.
In fanfiction, Naruto as the Seventh Hokage might also face some personal growth challenges. He has achieved his childhood dream, but now he might feel a sense of emptiness or wonder what's next. Some fanfictions could explore his spiritual journey. Maybe he goes on a solo mission to find a deeper meaning in his life and his role as Hokage. Or he could be trying to bring about a new era of ninja technology in the village, using his influence to encourage innovation in areas like medical ninjutsu or new types of jutsu development.
One common theme is legacy. Naruto has big shoes to fill as the Seventh Hokage, following in the footsteps of great leaders before him. Fanfictions often explore how he builds on their legacies and creates his own. Another theme is family. His role as a father and husband is important. We see how his family life impacts his decisions as Hokage. For example, he might make decisions to protect his family that also benefit the village.
Even Naruto himself could be a subject of this 'evil Hokage' concept in fanfiction. Maybe he is possessed by some dark entity or has a major change of heart due to some extreme event. This would completely change his character and turn him into an evil Hokage, which would be a very interesting and unexpected twist.
Another possibility is Naruto traveling back to his own childhood days. He could mentor his younger self, teaching him advanced jutsu and wisdom he's gained over the years. This would make his younger self much stronger much earlier, and might also change how he interacts with Sasuke. For example, he could help his younger self better understand Sasuke's pain and prevent some of their earlier conflicts.
Naruto himself could be a potential character, perhaps in a mentoring role to the 6th Hokage. Sasuke could also be there, maybe as an ally or a rival in some aspects of the story.
One plotline could be Naruto being transported to the Mandalorian universe. He has to learn the ways of the Mandalorians while still relying on his ninja skills. Another could be a Mandalorian coming to the Naruto world and Naruto teaming up with him, sharing their combat knowledge. For example, Naruto could teach the Mandalorian about chakra, and the Mandalorian could teach Naruto about their advanced weaponry.