A great plot could be that Bakugou and Deku get transported to an alternate universe where they don't know anyone and have to rely solely on each other. They face many challenges like finding food, shelter, and dealing with new 'quirks' in this universe. Through this adventure, they see sides of each other they never knew before and their friendship becomes unbreakable. Also, they could have a plot where they both enter a hero competition together as a team, and their teamwork surprises everyone including themselves, which strengthens their bond as best friends.
One plot idea could be that Bakugou and Deku are paired for a really difficult hero training mission. At first, they bicker as usual but then realize they need to work together. They start combining their quirks in unique ways and in the process, they become closer as friends. Another idea is that they have to protect a small village together from a powerful villain. During this, Bakugou learns more about Deku's selfless nature and starts to respect him even more, deepening their friendship.
One key element is the resolution of their past conflicts. Since they had a lot of rivalry in the original story, in a friends - based fanfic, they need to address those issues. For example, Bakugou realizing his wrong attitude towards Deku.
One great fanfic is 'The Road to Friendship'. It shows Bakugou slowly realizing Deku's worth and them building a bond through various challenges at UA. It has some really heartwarming moments like when they team up in a training exercise and start to understand each other better.
One possible plot could be that Deku has had a really tough day at hero training. He's doubting his abilities and feeling down. Bakugou, who has grown as a person, notices. He might start off a bit rough, like his usual self, saying something like 'Don't be such a crybaby, Deku!'. But then he actually sits down with Deku and shares some of his own insecurities about being a hero. He tells Deku that everyone has bad days and that he's seen Deku's progress and knows he's strong. This comforts Deku and they end up having a more understanding relationship.
Well, it could be that Bakugou finally realizes his true feelings for Deku after a long time of denying them. Maybe there was a big event that made him see Deku in a whole new light. For example, Deku saved Bakugou's life in a dangerous battle. And then Bakugou, who is usually so tough on the outside, struggles with his new - found emotions and finally musters up the courage to confess to Deku.
One possible plot is that Bakugou has been secretly in love with Deku for a long time. He observes Deku's kindness and growth, and it makes his heart flutter. He decides to propose when they are alone one day. He might start by reminiscing about their journey together, from being rivals to becoming something more, and then pop the question.
One popular plot idea is them working together on a difficult mission. They have to put aside their differences and combine their powers. Another is a story where Bakugou realizes his true feelings for Deku and struggles with how to express them. A third could be a fanfic where they are transported to an alternate universe and have to rely on each other to get back home.
A possible plot is a power struggle between them. Since Deku has turned villain, he might see Bakugou as a threat to his plans. Bakugou, on the other hand, wants to bring Deku back to the light. This creates a constant back - and - forth of battles, both physical and psychological, as they try to outwit each other.
One idea could be that Deku, turned villain, challenges Bakugou's view of heroism. He could expose the flaws in the hero society that Bakugou blindly believes in. For example, Deku might target the way heroes are ranked and how it creates a cut - throat environment. This would force Bakugou to re - evaluate his own pursuit of being the top hero.
One plot idea could be Percy and Annabeth going on a quest that has nothing to do with the main prophecies. They could be exploring an ancient, forgotten land just for the fun of it and to learn more about the world. Along the way, they face challenges that test their friendship like when Percy accidentally angers a local spirit and Annabeth has to use her wits to calm the situation.
Bakugou could use his words. He might tell Deku that he believes in him. For example, he could say 'Deku, you may be a nerd but you're a strong nerd.' It's a backhanded compliment but it shows he has faith in Deku.