From Pathfinder Lost Omens Ancestry Guide, which isn't enabled.

Aquatic Eyes

FEAT 1

As your connection to water grows, you can see more easily in places with less light, such as the depths of the ocean. You gain low-light vision, or you gain darkvision if your ancestry already has low-light vision.

Special If your ancestry has neither low-light vision nor darkvision, you can take this ancestry feat a second time to gain darkvision. You can't retrain out of this feat.

Pathfinder Lost Omens Ancestry GuideOGL