Shinsou is obviously really insecure if his quirk, so that could take a great toll on his mental health
Bakugo would be very insecure about people’s negative opinions about him, so for example someone saying todoroki is stronger than him. It could potentially lead him to overworking himself
Kirishima would be really insecure about who he used to be, so for example middle school and how he though he was plain like his quirk (which he isn’t)
Ochaco would be very insecure about her family status, she would do anything to stop people outside of her class from knowing she comes from a poor background and is only here for money to support her parents
Midoriya would be really insecure about his scars, if someone were to touch his scars especially in his upper arm he would flinch really hard and begin distance himself so people don’t touch him.
Kaminari would be insecure about short circuiting his brain since he always gets laughed at, it makes him feel dumb so he only does it when he needs to protect someone or on accident
I hope that helped!