One possible plot could be that the Big Three - Mirio, Nejire, and Tamaki - are transported to an alternate universe where they have to team up with their counterparts from different versions of BNHA. They face new villains and challenges that require them to combine their unique quirks in unexpected ways. For example, they might encounter a villain who can manipulate time, and they have to figure out how to use Mirio's intangibility, Nejire's wave motion, and Tamaki's transformation quirks to stop the villain before he destroys the fabric of the universes.
Midoriya could be an interesting addition. His growth and determination would contrast well with the Big Three. He could learn from their experiences and they could be inspired by his never - give - up attitude. Another character could be Bakugo. His explosive personality and powerful quirk would add a lot of drama and action to the story. His rivalry with the Big Three, especially Mirio, could create some intense moments.
One idea could be focusing on their training together. Maybe they have a special training session where they learn new techniques from each other. Another idea is to explore their relationships outside of hero work, like how they are as friends in normal, everyday situations. For example, going to the movies or having a meal together.
One idea could be that the characters from Bnha are transported to the Warrior Cats world. For example, Deku could find himself in a Clan and have to learn the ways of the cats to survive. He might use his quirk in unique ways to help the Clan, like using One For All to jump really high to catch prey or to defend against other Clans.
Begin by deciding on the tone of your fanfic. Do you want it to be action - packed, humorous, or more of a character - study? Once you've decided that, create an outline. Outline the main events that will happen, like if you want the 'big three' to face a new villain, write down how they will encounter the villain, what the fight will be like, and how they will ultimately defeat or deal with the villain. Also, don't forget to give each character their moment to shine.
In 'bnha kny crossover fanfiction', a prevalent theme is the clash of cultures. The very different worlds of My Hero Academia, with its modern superhero society, and Demon Slayer, which is set in a more historical - fantasy Japan, create interesting scenarios. There's also the theme of adaptation. Characters from one universe have to adapt to the rules and norms of the other. For instance, heroes having to deal with the existence of demons, or demon slayers trying to understand the concept of quirks. Additionally, friendship and cooperation across the two universes is often explored as a theme.
One idea could be to have the characters from BNHA attend the Death Weapon Meister Academy in the Soul Eater universe. They could learn about soul resonance and how to handle weapons in a whole new way. For example, Deku could be paired with a unique weapon and struggle to master the new techniques.
Next, when writing the crossover, focus on how the characters would react to the new environment. If Bakugo were to enter the Soul Eater world, he'd probably be very frustrated at first with all the new rules. You should also make sure to balance the elements from both series. Don't over - emphasize one over the other. For example, give equal importance to the development of BNHA - style quirks and Soul Eater - style soul abilities.
A Tsunade crossover in BNHA fanfiction could involve her being from a different world but getting involved in the BNHA universe's affairs. She might end up in a fight against some of the villains. Given her short temper, she could be quite a force to be reckoned with. She could also form alliances with some of the heroes like All Might, sharing her knowledge of combat and medicine.
Tsunade could interact with Midoriya Izuku. Izuku is always eager to learn new things and improve his skills. Tsunade could see his determination and potential, and she might teach him some of her combat and medical knowledge. Maybe she would help him control his quirk better or give him some physical training tips.