This came to my mind: https://en.wikipedia.org/wiki/Throat_microphone

Obviously for everyday, casual use that would require some design work. Maybe integrate that to jacket or shirt, if the hardware is not too expensive. Bluetooth for communications. Battery is a bit of a problem, having to constantly charge my jacket is not something I would like to do. Maybe there would be some opportunities to build it so that it would not be active all the time.

Or maybe one should actually rethink the whole concept. Maybe it would be better to just capture the vibrations from few places around the throat and then use machine learning to make sense of them instead of trying to use the traditional speech recognition.