Lullaby of the Drowned by n7punk

Adora and Catra were raised in the Pirate Horde together all their lives. After a lifetime of being told she would amount to nothing, Catra has finally been given her own ship to command – it only took Adora’s ship sinking for Shadow Weaver to give Catra a chance. Avenging her lover is the only way Catra can imagine ever feeling at peace again. It is odd how familiar the siren they are hunting looks, though.
(Pirate Catra/Siren Adora AU)