Is there a way to control a Mac's audio volume from Apple Watch? Apple didn't provide Watch functionality for system-wide Mac volume adjusting as far as I know.
NB: The only so-so way I've found is if audio is playing from Mac iTunes, and the iPhone/Watch is paired with that library via Home Sharing. The volume can then be changed with the Watch Remote app – but that doesn't trigger system-wide volume. It only changes iTunes' in-app volume.
Is there some third-party software for iOS/WatchOS that can accomplish this?
Note about iPhones: I know that the iOS app BTT Remote can control a Mac's volume, but unfortunately there is no Watch app for it.