Well, it could start with a Wakfu character accidentally opening a portal to the Naruto universe. Some of the Wakfu heroes might be intrigued by the concept of chakra and ninjutsu. They would then bring Naruto and his friends back to their world. In this crossover, Sasuke could find similarities between his search for power and some of the power - hungry characters in Wakfu. And the battles would be epic, with a mix of ninja techniques and Wakfu spells. Maybe Naruto would even try to learn some basic Wakfu magic, and hilarity or amazing new power combinations could ensue.
Well, it could start with Inuyasha being curious about the strange powers he senses, which turn out to be Naruto's chakra. He tracks it down and meets Naruto. At first, they might be a bit wary of each other, but then they realize they have a common goal of protecting their respective worlds. They then combine their skills. Naruto could teach Inuyasha some ninja stealth techniques, and Inuyasha could show Naruto how to better sense spiritual energy.
Imagine if there was a tournament that brought the best fighters from both universes together. Naruto, Sasuke, and the others from the Naruto world, and Kai, Jay, and the rest from Ninjago. They start off competing against each other but then realize there is a greater threat lurking. A group of shadowy figures wants to steal the powers of both ninjas and warriors. So, they must put aside their differences and combine their skills to fight this new enemy.
The plot could involve a threat that requires the combined efforts of both universes. Maybe an ancient evil that can only be defeated by the unique powers of Naruto characters and the technology and superpowers of Marvel heroes. For instance, a villain who can absorb all forms of energy is threatening both the ninja world and the Marvel universe. Naruto and his friends team up with the Avengers to stop this threat. Along the way, they have to learn to work together, which could lead to some interesting character interactions, like Naruto trying to understand Stark's high - tech gadgets or Thor explaining his Asgardian magic to the ninja.
The plot could involve a common enemy that both Naruto and Beelzebub have to face. For example, a powerful demon that threatens both the ninja world and the world of Beelzebub. Naruto's determination and Beelzebub's unique abilities would combine to take on this threat. They might start off as rivals, not trusting each other at first, but as they face challenges together, they form an alliance. Naruto could show Beelzebub the value of friendship and loyalty, which are important themes in his own world.
The plot could involve Naruto characters in a Disney - like world. For example, Naruto might find himself in the world of 'Frozen' and team up with Elsa to stop an evil jutsu - using snow monster. He could use his Rasengan against the icy threats while Elsa uses her ice powers to assist him. This would be a cool mix of the ninja - like action from Naruto and the magical, fairy - tale setting of Disney.
Well, it could be really interesting. Maybe Naruto and his friends somehow end up in the world of Dog Days. Naruto might be confused by the different rules and the animal - like characters. He could use his ninja skills in unique ways there. For example, his shadow clone jutsu could be used to create distractions during battles in Dog Days' world. And his determination to protect his new friends in this strange land could drive the story forward.
Naruto's chakra - based abilities like Rasengan could interact interestingly with Wakfu magic. Maybe the Rasengan could be enhanced by infusing it with certain Wakfu elements. On the other hand, Wakfu spells might be disrupted by Naruto's strong chakra flow. For example, a spellcaster in Wakfu might find it difficult to cast a spell when Naruto is nearby releasing a large amount of chakra.
The plot could involve Naruto characters in the Assassin's Creed world. Maybe Naruto himself could be an assassin with his ninja skills. He'd be sneaking around ancient cities, using his shadow clones to distract guards just like assassins use decoys. It would be really cool to see him climb buildings and assassinate targets in a more historical and different setting than the ninja villages.
A Gintama and Naruto crossover fanfiction could be really interesting. It might start with Naruto characters somehow ending up in the Gintama world. Maybe Naruto and his friends are on a strange mission and get sucked through a portal into Edo. They would be shocked by the wacky and modern - yet still somewhat feudal - nature of the Gintama world. Gintoki could mistake them for some new weirdoes in town. And then there could be all kinds of chaos as Naruto tries to use his jutsu, which might have unexpected effects in the Gintama universe due to its different rules of physics and such.
In this crossover fanfiction, the art styles could also blend in an interesting way. The distinct anime - like look of Naruto characters against the more urban and gritty style of the Boondocks. Story - wise, perhaps there's a common enemy that both Naruto and the Boondocks characters have to face together. It could be someone who wants to disrupt both the ninja world and the Boondocks' community, forcing them to team up and use their combined skills and knowledge to defeat it.