First, make the characters misunderstand each other's powers. For example, a Naruto character might mistake a Bleach character's reiatsu for some kind of strange chakra. This can lead to comical situations where they try to figure out how to work together. Another way is to give them shared goals that require different skills from each universe. So, a Bleach character's ability to sense spiritual energy and a Naruto character's tracking skills could be combined to find a hidden treasure in the crossover world.
Definitely Naruto and Ichigo. They are both strong - willed protagonists. Naruto's positive and determined attitude could clash and then blend with Ichigo's more brooding and intense personality. It would be interesting to see how they communicate their different fighting styles and powers to each other.
You can start by highlighting the differences in the characters' personalities. For example, if one Pretty Cure is really shy and another is outgoing, their first meeting can be full of awkward but cute moments. Maybe the outgoing Cure tries to befriend the shy one right away and the shy one is a bit hesitant at first.
Naruto and Ruby would be really interesting. Ruby is young and full of energy, much like Naruto. They could bond over their shared enthusiasm for protecting others. Naruto could show Ruby some of his cool ninja moves, and Ruby could introduce Naruto to Crescent Rose. Another interesting interaction would be between Sakura (from Naruto's harem) and Weiss. Weiss is from a wealthy family and is very proper, while Sakura is a strong - willed medical ninja. They could have some really fun arguments and also learn from each other's skills.
Goku and Aizen would be an interesting pair. Aizen is a master manipulator, and when he first encounters Goku, he would try to use Goku for his own ends. But Goku, being pure - hearted, would see through Aizen's schemes. Their interactions would be a battle of wits as well as power. Goku's straightforward nature would be a contrast to Aizen's devious ways, and it would be fascinating to see how Goku would deal with Aizen's illusions and mind games.
Itachi and Toshiro Hitsugaya could have a very deep and thought - provoking interaction. Itachi, with his complex past and his sacrifices, might make Hitsugaya reflect on his own sense of duty. Meanwhile, Hitsugaya's strict sense of justice could make Itachi question some of his own actions. Also, Hinata and Orihime could bond over their shyness and their strong feelings for their respective love interests.
Definitely Naruto and Tohka. Naruto's exuberant and positive personality would contrast with Tohka's more straightforward and sometimes naive nature. They could have some really fun exchanges, like Naruto trying to teach Tohka about ninja values and Tohka showing Naruto her unique way of enjoying food. It would be an interesting dynamic to explore.
Sakura and Pearl could also have an interesting dynamic. Sakura is a strong - willed kunoichi who has worked hard to become a great healer and fighter. Pearl is elegant and highly skilled in combat. They could exchange their knowledge of combat techniques and healing methods. Pearl could teach Sakura some of the more refined Gem - style fighting moves, and Sakura could show Pearl how to use her medical skills in more practical and efficient ways during a fight.
The interaction between Naruto and Boomhauer could be really cool. Boomhauer has his own unique way of talking which Naruto would probably find really strange at first. But as they get to know each other, Naruto might start to understand Boomhauer's wisdom hidden behind his mumbling. And Boomhauer might be impressed by Naruto's loyalty and determination, which are traits he can respect despite Naruto being from a completely different world.
Another important aspect is the goals of the characters. Ash wants to become a Pokemon Master, while the Digimon Tamers often aim to protect the Digital World. If their paths cross, they might initially have different priorities. But as they face common threats, they start to understand each other's goals and work together. This change in attitude towards each other's goals can create deep and believable character interactions.
Ichigo and Sasuke would also make a great pair. Both are complex characters with a lot of power. They have a similar drive to become stronger and protect their loved ones. In a crossover, they could start off as rivals, constantly trying to outdo each other in combat. But as they face greater threats together, they could develop a mutual respect and perhaps even a friendship, sharing their combat techniques and knowledge of their respective worlds.