2-Way Wireless rechargeable Headphones

I'm looking for everything needed to send directly to prototyping companies ie., accurate design/s to create a working prototype. The headphone's main selling point is: the wearer/user/Grandpa is able to communicate with nearby people/Grandma while watching TV without having to remove the headphones, find and put in their hearing aids, to reply. It needs to have the capability/function of muting or overriding the incoming TV sound when spoken to. Preferably this would happen automatically when 'Grandma' needs to speak to 'Grandpa' and she would only need to speak. Let's call this Near Voice Override" NVO. Although there could be a programmable voice command that Grandma says to activate, let's call this the "Near Voice Command Activation" function (NVCA) that mutes the TV sound so that the microphone that's built into the headphones to receive external sound, delivers an amplified (adjustable?) sound from a nearby voice. The last and unpreferred option would be a button that the user/wearer/Grandpa pushes to mute the incoming television sound and activate the microphone to hear the nearby voice/Grandma The aesthetic design should be comparable to existing headphone systems on the market with a base charger. *The "Near voice override" (NVO) functionality using a built-in microphone would be the only difference from the standard. I'm not sure what kind of engineer I'm looking for and/or if I need multiple engineers to get the concept designed and ready for prototyping so any & all input is welcome and much appreciated.