It’s aimed at detecting nocturnal snores and coughs.
The feature will apparently come to the Digital Wellbeing suite.
Update: September 5, 2022 (2:22 AM ET): We now have a better idea of how Google plans to implement snore and cough detection on Android phones. 9to5Google dug into a beta version of the Digital Wellbeing app and discovered references to cough and snore detection in it.