One main theme is cuteness. Writers often focus on making baby Bakugou as adorable as possible, with his chubby cheeks and tiny hands. For example, in many fanfics, he'll be toddling around and getting into harmless mischief.
There could be fanfics where Bakugou's baby has some unique quirk. In these stories, Bakugou has to deal with the challenges of raising a child with a powerful and perhaps dangerous quirk. It could involve him training the baby in a safe way while also shielding it from the wrong kind of attention.
You can try fanfiction websites like Archive of Our Own (AO3). There are a large number of fanfics there, and you can search specifically for 'bakugou baby fanfic'. Just type in the relevant keywords in the search bar, and it will show you a list of stories related to it.
One popular baby Bakugou fanfic is 'Baby Steps'. It shows Bakugou in a really cute and innocent light as a baby, with his character traits still somewhat visible even at that young age.
One idea could be '5 Times Bakugou Saved the Day'. It would show his heroic side as he uses his powerful quirk to rescue people in different dangerous situations. Another idea is '5 Moments Bakugou Realized His Mistakes', which would focus on his character growth.
A '5 times bakugou fanfiction' could be really interesting. It might explore five different emotional states of Bakugou. One time could be when he was extremely angry and how that affected his actions. Another time could be when he was vulnerable, perhaps after a difficult battle. Then there could be a time when he was happy and celebrating a victory. And two more times could be related to his growth as a character, like the first time he realized he needed to change his attitude towards his friends, and the second time when he actually made a significant change in his behavior.
Bakugou might react with his usual anger. He could lash out at the bullies verbally or even physically, which might make the situation worse. For example, if someone makes a snide comment, he could respond with a loud and aggressive retort.
Midoriya is often a common character. Since he has a complex relationship with Bakugou, his reaction to Bakugou's expulsion can be an important part of the story. All Might might also be included as he could be a mentor figure who tries to guide Bakugou, even after his expulsion. And Bakugou's other classmates like Kirishima would likely be there too, as they are his friends and would be affected by his leaving.
All Might would probably be one of the first to try to stop Bakugou. As Izuku's mentor and a symbol of justice in the story, he wouldn't tolerate such violence. Another could be their teacher, Aizawa. He's strict and protective of his students, so he'd surely step in.
Well, Bakugou's development in Bakugou One For All fanfics can be quite complex. Initially, he might struggle with the idea of having a power that wasn't his own. But as the story progresses, he starts to adapt. He becomes more empathetic as he realizes the sacrifices that were made for One For All to be passed down. His relationships with his mentors, like All Might, also change. He becomes more receptive to advice and starts to see the bigger picture of being a hero, not just in terms of strength but also in terms of character and leadership.