Start listening without a wake word?

Thinking of trying the local voice control, more like wanting to but can’t find the equipment to do it, and I’m wondering if there’s a way to have it “listen” without waking it, but rather by another trigger?
For sake of simplicity let’s say I open my front door, can the door sensor be used as a “wake word” ?
Or any other way?

certainly using and ESPHome device you could do this quite simply.

How about without ESPHome? Many of us went the route of the wyoming satellite tutorial, since it’s advertised as among the more painless options.