Muting on apple watch
Can I mute a group text on apple watch but continue to receive all other notifications?
Apple Watch
No. At this time, the ability to mute a group conversation is not available on the watch. Even if you have your notifications set to mirror the iPhone and you hide alerts on the phone, it does not change things on the watch.
Feedback to Apple about a desire to see this change can be made here, Feedback - Apple Watch - Apple