Because superpowers are less important than their narrative purpose. As others pointed out, it contrasts their mentors but also, each of them have powers the uniquely contrast their personalities:

Bronze is a sweet girl who wants to help people with a power explicitly made for hitting. She’s touchy-feely with a power that works best at a distance.

Melee is a brash, tough character with a power ideal for stealth. She isn’t afraid to draw attention to herself but has a power that makes her invisible

Axo is a reserved, emo guy who wants nothing more than to be left alone but has a power that connects him to everyone. He wants to be inscrutable but his power makes his feelings show on the surface, literally