Another concept is a story where fem Goku and Naruto meet as children. Fem Goku, being used to the harsh training on her own planet, helps Naruto train in a more intense way. This could lead to Naruto developing new forms of his jutsu earlier than in the original story. And as they grow up, they continue to have each other's backs, facing different threats in their respective worlds together.
A fanfiction could revolve around a tournament in which both Naruto characters and fem Goku participate. The story could focus on the cultural differences between the two groups. For example, how Naruto's ninja skills compare to fem Goku's ki - based attacks. And also how they interact and form teams during the tournament, with some interesting match - ups and unexpected alliances.
One idea could be a story where fem Goku is somehow transported to the Naruto universe. She might use her Saiyan strength and abilities to help Naruto and his friends in a big battle against a powerful enemy like Madara. Maybe she teaches Naruto some new combat techniques inspired by her own training on Planet Vegeta.
Perhaps Goku lands in New York City and his power level is sensed by the Avengers. Iron Man is initially skeptical but Captain America is more open - minded. They test Goku's abilities and find out he can move at incredible speeds and has near - invincible defenses. So they ask him to train the Avengers in new combat techniques, which leads to some humorous and action - packed training sessions.
One idea could be to have characters from Naruto end up in the world of Danmachi. For example, Naruto himself could find his way into the dungeon and his ninja skills would be put to the test against the dungeon monsters. His shadow clone jutsu could be used in interesting ways, like sending clones into different dungeon levels to scout or fight. Another idea is to have the concept of chakra introduced into the Danmachi world. This could change the way adventurers fight and level up. Maybe some of the Naruto characters could train the Danmachi adventurers in new combat techniques.
One idea could be a crossover where Naruto is somehow transported to the Star Wars universe and meets Padme. Maybe he uses his ninja skills to protect her from the Sith.
Another concept is that Naruto is sent to Middle - earth. There, he could use his ninja skills and chakra powers. He and Gandalf could team up to fight Sauron. Naruto's ability to make friends and inspire others would be really useful in uniting the different races of Middle - earth against the common enemy.
A more complex idea is that the Matrix is used to create a virtual training ground for the shinobi. They enter the Matrix to practice their skills in a more controlled environment. However, they soon realize that there are some dark secrets within the Matrix, and Naruto has to lead the way to uncover the truth and free those who are trapped inside.
Another possibility is that Naruto visits the Townsville, the city where the PPG live. He might be confused by the modern technology there compared to his own world. The PPG could teach him about it while he shows them some of his ninja skills like tree - climbing and water - walking.
A third idea could be a story where Naruto's clones are mistaken for some kind of superpower by the Thundermans. Max might be intrigued and try to figure out how to do it himself. Meanwhile, the Thundermans could teach Naruto about modern technology which he has never seen in his own world. This could lead to some really interesting and comical situations as they try to understand each other's worlds.
Another possibility is that Pokemon exist in the Naruto world. Some ninja could have Pokemon as partners instead of traditional ninja animals. For example, Sasuke could have a Dark - type Pokemon like Umbreon that would match his cool and mysterious personality. And the Pokemon battles could be incorporated into the ninja battles, adding a new layer of strategy.
One idea could be a crossover where Naruto characters gain the abilities of Needless characters. For example, Naruto could get the power of Adam Blade's regeneration. It would be interesting to see how he uses it in battle, especially against tough foes like Pain or Madara.
Another concept could be a fusion of their powers. Imagine if Naruto was somehow able to absorb Frieza's power or vice versa. This could create a new and extremely powerful being. The story could explore how this new entity would interact with the two different universes. Would it be a force for good or would the power corrupt it? There could be a lot of internal conflict as the combined Naruto - Frieza entity struggles with its new identity and purpose.