No way. The manga portrays their connection through mutual respect and competition in their journey to become great heroes. A kiss is not part of that narrative at all.
In some fanfictions, Bakugo can become more empathetic. For example, if he experiences a situation where he realizes the pain he's caused Deku over the years. His aggressive nature might soften as he starts to understand Deku better. Deku, on the other hand, could become more assertive. Instead of always being the timid one, he might stand up to Bakugo more firmly in fanfiction scenarios.
One common theme is friendship. Despite their initial rivalry, fanfics often explore how Bakugo and Deku form a deep bond. Another theme is growth. They both grow as heroes and as people in these stories. For example, Bakugo learning to control his temper and Deku getting stronger.
One interesting Deku and Bakugo fanfiction could be where they have to team up for a special mission that no one else can handle. In this story, they start off bickering as usual but gradually learn to trust and rely on each other more deeply.