My plea / request : Make a home assistant a DROP IN replacement for a standard light switch. It has power, its adds functionality from the get-go (smart lighting), it’s placed in a convenient position for the room and no extra wires etc required.
Look at Shelly light switches.
You've misunderstood what they're asking for. They're asking for Home Assistant hardware (microphone, speaker, wifi) that, instead of being a standalone box taking up space on the counter/table/etc, fits into the hole in the hall where they currently have a lightswitch.