Midoriya and Nagisa would be an interesting pairing. Midoriya is all about becoming a great hero and has a powerful Quirk that he's constantly learning to control. Nagisa, on the other hand, is a skilled assassin - in - training with great stealth. They could learn a lot from each other. Midoriya could teach Nagisa about the importance of having a big dream and standing up for what's right in a more heroic sense, while Nagisa could show Midoriya how to be more stealthy and observant.
All Might and Koro - sensei would be a really unique pairing. All Might is the symbol of peace in the Bnha world, while Koro - sensei is the unkillable teacher in the Assassination Classroom. They both have a strong sense of responsibility towards their students. All Might could be intrigued by Koro - sensei's unique situation and abilities, and Koro - sensei could learn from All Might's heroic ideals. Their combined presence would surely have a huge impact on the students from both universes in this fanfiction.
I think Ruby and Nagisa would be a great pairing. Ruby is all about being a hero and has her own sense of justice, while Nagisa has been trained to be an assassin but also has a good heart. Their different outlooks could lead to some really interesting conversations and adventures.
Tanjiro and Deku would be a great pairing. Tanjiro's strong sense of justice and determination to protect his loved ones is similar to Deku's. They could learn a lot from each other, with Deku showing Tanjiro about quirks and Tanjiro teaching Deku about breathing techniques. Another interesting pairing could be Bakugo and Inosuke. They both have a fiery temper and are very competitive. Their interactions would be full of energy and probably a lot of arguing at first.
Naruto himself would be really interesting. His never - give - up attitude could inspire the students in the Assassination Classroom. He could also learn from their unique skills and knowledge. His journey in this new world would be full of surprises as he tries to adapt to their assassination - based curriculum.
One interesting pairing could be Midoriya and Spider - Man. Both are young heroes who are constantly striving to prove themselves and have a strong sense of responsibility. They could learn a lot from each other's experiences and fighting styles.
One idea could be that the students from Bnha are sent to study in the Assassination Classroom for a special mission. They have to learn assassination skills while also trying to incorporate their own Quirks into the training. Another plot could involve a villain who has abilities similar to Koro - sensei from Assassination Classroom threatening the Bnha world, and the heroes from both universes have to team up to stop him.
Definitely Nagisa. In the crossover, he could be the one who has the hardest time adapting to the new world of KHR. His assassin skills would be put to the test in a different way compared to Assassination Classroom. He might form an interesting friendship with Tsuna, as both are somewhat timid at first but have great potential within them.
Ladybug and Deku would be a great pairing. Ladybug is a strategic and powerful leader in her world, and Deku has his own unique way of analyzing situations and his determination. Together, they could share their knowledge about combat and heroism. Deku could learn from Ladybug's experience with magic - based powers, and Ladybug could learn about different Quirks from Deku.
I think Tai and Alice would make an interesting pairing. Tai's leadership skills from the Digimon world could be put to the test when dealing with Alice's curious and often dreamy nature. They could learn a lot from each other, like Tai could teach Alice about courage in the face of danger, and Alice could show Tai the beauty of imagination.
Weiss and Val/entina could be a great pairing. Weiss, with her refined and aristocratic upbringing, might initially clash with Val/entina's more street - smart and sassy attitude. But as they get to know each other in the fanfiction, they could find common ground in their determination and strong - willed natures. They could also share combat techniques, with Weiss teaching Val/entina about Dust - based attacks and Val/entina showing Weiss some of Genlock's hand - to - hand combat moves.
Naruto and Shrek would be an interesting pairing. They are both very different yet share some common traits. Naruto is full of energy and determination to protect his village, while Shrek just wants to be left alone in his swamp but also has a big heart. Their interactions would be full of humor and also moments of understanding as they come from different worlds but have similar values in a way.