A Song Below Water by Bethany C. Morrow

Legacies meets Nic Stone’s Dear Martin in Morrow’s YA fantasy debut: best friends discover their magical identities against today’s challenges facing young black girls
Tavia is already at odds with the world, forced to keep her siren identity under wraps in a society that wants to keep her kind under lock and key. Nevermind she's also stuck in Portland, Oregon, a city with only a handful of black folk and even fewer of those with magical powers. At least she has her bestie Effie by her side as they tackle high school drama, family secrets, and unrequited crushes.

But everything changes in the aftermath of a siren murder trial that rocks the nation; the girls’ favorite Internet fashion icon reveals she's also a siren, and the news rips through their community. Tensions escalate when Effie starts being haunted by demons from her past, and Tavia accidentally lets out her magical voice during a police stop. No secret seems safe anymore— soon Portland won’t be either.