Perhaps the Sharingan ability from Naruto could be passed on to a character in MHA, and they have to deal with the new power and the consequences that come with it. In reverse, a quirk could be transferred to a Naruto character. This would create a situation where the characters have to figure out how to use these new powers in their own worlds. It could also lead to some interesting battles and alliances as they try to master their new abilities.
One idea could be that Naruto characters visit the MHA world and have to adapt to the modern society and different power system. For example, Naruto might be intrigued by how quirks work compared to chakra. Another plot could involve villains from both universes teaming up, forcing the heroes from Naruto and MHA to collaborate. They would need to combine their unique fighting styles and powers to defeat the combined threat.
One idea could be that the Avengers are somehow transported to the MHA universe. They have to deal with quirks while also trying to find a way back home. Maybe they team up with the students at UA to fight a common villain who has a power that combines both advanced technology and a powerful quirk.
Another possibility is a crossover with the world of Naruto. The characters from MHA could participate in the Chunin Exams. Bakugo might be really into showing off his skills in this new and different kind of competition.
One idea could be that the heroes from MHA are transported to the Super Sentai world and have to team up with the Sentai warriors to fight a common enemy that is threatening both universes. Maybe a powerful villain has found a way to cross dimensions and is causing chaos.
One possible title could be 'My Hero Academia in the World of Attack on Titan'.
Maybe there's a plot where a powerful and rare Pokemon is causing chaos in the Naruto world. The Naruto characters have to team up with some expert Pokemon trainers from the Pokemon world to stop it. Naruto could learn about the unique bond between trainers and Pokemon and apply some of those concepts to his relationships with his friends. And the Pokemon trainers could be in awe of the ninja techniques and use some of that knowledge to improve their own strategies.
A possible plot is that the Zoids themselves gain some of the abilities of Naruto characters. Imagine a Zoid being able to use chakra and perform ninjutsu. A Fire - type Zoid could use the Fireball Jutsu. This would completely change the dynamics of Zoids battles. Also, the story could revolve around a group of Naruto characters trying to stop an evil force in the Zoids world that is using Zoids in a way that could destroy both the Zoids world and the Naruto world. They would have to learn about Zoids and team up with local Zoid pilots to fight against this common enemy.
One idea could be a character from Naruto ending up in the Descendants' world. For example, Naruto himself could be transported there. He might use his ninja skills to deal with the challenges in the Descendants' world, like facing off against the villains in a very different way compared to the Descendants' characters. Maybe he'd use his shadow clone jutsu to confuse the bad guys or his Rasengan to take on powerful foes.
One idea could be that members of Root are sent to infiltrate the Hidden Leaf under the guise of being friendly shinobi. They cross paths with Naruto and his friends. Naruto, being the perceptive one, senses something off about them. This could lead to a series of battles and mind games as Naruto tries to expose their true motives.
Maybe there's a crossover where the Kyuubi's chakra has some strange effect on the Gargoyles. It could either enhance their powers in unexpected ways or cause some sort of chaos that they have to work together to fix. For example, the Kyuubi's chakra might accidentally awaken an ancient evil in the Gargoyles' world, and Naruto and the gargoyles must use their combined strength and wits to stop it.
Maybe in this crossover, Naruto has a vision of the Traveler from Destiny. Curious, he somehow manages to cross over to the Destiny universe. There, he meets the different classes of Guardians. He could learn about their weaponry and powers and in turn, teach them about chakra. They could then work together to stop a Vex invasion that is spreading across both universes.