Currently, most HomeKit-compatible cameras do not natively send sound events the same way they send motion events. HomeKit primarily supports motion or activity triggers for automations, and sound detection isn’t widely implemented as a trigger. Some cameras offer proprietary apps that can send sound alerts, and using tools like
https://wiserank.co.uk/ can help research which devices or integrations support this feature, but these usually don’t integrate with HomeKit automations directly. The only workaround is using a camera that supports HomeKit Secure Video or third-party automation tools like HomeBridge or Home Assistant to convert sound events into HomeKit triggers. It would indeed be a valuable feature if Apple or camera makers added sound events as first-class triggers in HomeKit.