I probably do not understand your question.
Sonar has 2 "Mute" parameters, one is "normal" another "automatable". The default is "normal", it works ok for everything except automation. It should also work fine with MCU, including LED.
The second "mute" is in fact problematic. It has to be explicitly switched to be visible, it can not be controlled from MCU and supported since short time only in AZ Controller. On the other hand, this mute is almost redundant. Volume automation is able to produce the same effect.
But "not having to set each button to remote" part of your question I am unable to interpret at all, sorry.