Zoro and Yami. Both are badass swordsmen. Zoro's calm and collected fighting style compared to Yami's more brash and powerful style would create some interesting sparring scenes. They could exchange sword - fighting techniques and learn from each other. Yami might teach Zoro some of his dark magic - infused sword attacks, while Zoro could show Yami new ways to use his three - sword style more effectively.
Natsu and Asta would definitely have an interesting interaction. Natsu is all about his dragon - slayer magic and has a fiery personality. Asta, on the other hand, has no magic but his anti - magic swords make him a formidable fighter. They would probably start off challenging each other, but then realize they can learn from one another. Natsu could teach Asta about the power of raw magic, while Asta could show Natsu the importance of determination without relying on traditional magic.
Tsuna from Khr and Luffy from One Piece would be really interesting. Tsuna is initially a bit timid but grows into a strong leader, while Luffy is a fearless and carefree leader. Their different leadership styles could lead to some hilarious and also inspiring interactions. They might learn from each other's ways of handling their crews.
I think Naruto and Sanji would have some really cool interactions. Sanji would be both fascinated and a bit jealous of Naruto's strength. He might try to cook special meals for Naruto to boost his power even more. And then there's Usopp and Naruto. Usopp could be in awe of Naruto's abilities and might even try to incorporate some of Naruto's ninja tricks into his own arsenal of lies and actual combat skills. Also, Naruto and Nami could team up to strategize against enemies, with Nami using her knowledge of the world and Naruto using his combat experience.
Definitely Sam Winchester and Sebastian. Sam is always so morally conflicted in Supernatural, and Sebastian is a demon with his own code. Sam would likely be both intrigued and repulsed by Sebastian. He might try to figure out if there's a way to save Sebastian's soul, while Sebastian would be amused by Sam's naivete in thinking a demon can be redeemed.
I think Gray and Sanji would have some hilarious interactions. Sanji would be all over any female characters around, which would probably annoy Gray. At the same time, Gray could show Sanji some of his ice - make magic, and Sanji could cook some amazing food for Gray. Also, Happy and Chopper would be really cute together. They could both get into all sorts of mischief, like stealing food from the kitchen or exploring new islands. And Gildarts from Fairy Tail and Shanks from One Piece could have a really interesting conversation. They are both powerful and respected in their respective worlds, and could exchange stories about their adventures.
Ciel and Spider - Man could have a great interaction. Ciel's dark past and his determination to achieve his goals could be an interesting foil to Spider - Man's more light - hearted and responsible nature. They could learn from each other, with Ciel learning about the importance of using power for good, and Spider - Man getting a taste of the more cut - throat world Ciel comes from.
Saitama and Albedo would have really interesting interactions. Albedo is so devoted to Ainz in Overlord, and when she meets Saitama, who is just this nonchalant super - powerful guy, she would be both confused and perhaps a bit threatened. Saitama, on the other hand, would just see her as another person in this strange new world.
Definitely Saitama and Deadpool. Deadpool would be constantly trying to break the fourth wall and make jokes, while Saitama would just be there with his usual blank expression. It would be hilarious to see how Saitama reacts to Deadpool's non - stop chatter.
Another interesting interaction could be between Gwen (from Ben 10) and Nami (from One Piece). Gwen's intelligence and magical abilities would contrast with Nami's skills in navigation and her love for treasure. They could exchange knowledge, with Gwen teaching Nami some basic magic spells in exchange for Nami teaching Gwen about navigation techniques across the Grand Line.
I think Luffy and Spider - Man would be really interesting. Luffy with his carefree and fearless nature, and Spider - Man with his witty remarks. They would probably get along well and have some crazy adventures together.