on $*:TEXT:/^[!.]mute/Si:#:{
  if ($nick ishop # || $nick isop #) mode $chan +b-vh ~q: $+ $address($$2,2) $2 $2
}

on $*:TEXT:/^[!.]unmute/Si:#:{
  if ($nick ishop # || $nick isop #) mode $chan -b ~q: $+ $address($$2,2)
}

OR...

on @$*:TEXT:/^[!.]((?:un)?mute)/Si:#: {
  if ($nick(#,$nick,oh)) mode # $iif($regml(1) == mute,+b-vh ~q: $+ $address($$2,2) $2 $2,-b ~q: $+ $address($$2,2))
}