Continuing the discussion from Home Assistant and Google assistant : how to link HA buttons and Google automation:
Is the lack of a Button domain in Google Assistant a Google thing or a Home Assistant thing?
The button entity as exposed by ESPHome are excellent and work better for a momentary switch than a switch entity, but the Google Assistant doesn’t understand them.
That. See what Google supports as “traits” below.
I could imagine it could be mapped to a Google “Scene”, though, or anything similar for which Google doesn’t require a state.
Ok, thanks. Just need to expose a switch as well from the ESPHome device.
I believe there is a button domain, I saw that in release notes a few versions ago, don’t think the docs are updated … Lots of PR for button domains
Certainly doesn’t work from HA currently.
Hmm, should be?
Odd. I just get an “I don’t understand” response. I wonder what the right phrase is for a button? “Press” doesn’t seem to work. Neither does “open/close” or “on/off”.
cant help with that, the integrtation i use dont have button support, so untill now i cant expose buttons yet…
do you see buttons in the google app when you expose them ?
As buttons are translated to “scenes” in Google, maybe “activate” or similar?
that would be stupid 
What, that Google doesn’t have a notion of stateless button and that HA worked around it by using the only stateless thing available, i.e. “scenes”? Your opinion…
Maybe calling the thing “button” in HA wasn’t the brightest idea, though…
Well, if want to turn something on “stateles”, i just expose stateless switches
A switch always has a state 
This “button” was explicitly created in HA because there was no “stateless” entities previously.
yeah, i know, but was able to turn something on, if it was already on
ao actually the state in Google is always OFF => so i just always turn in on => and then the state goes back to OFF
like a button you press
Anyone find the key word yet? They are indeed scenes, how to poke them is the question.
Update…
Never mind. Figured it out. You have to set-up a Google Home App Routine to trigger the scene, so another layer of programming to go bad.
Switching mine back to an input_boolean.
I have to turn them back off, but at least all the code is in one place.
Perhaps my Earlier post could be marked as the solution, that is now that Buttons are Google Scenes…
In ESPHome I create both a button and a switch. Button for the dashboard, switch for Google to operate
I created a Google home routine for my input_button but unfortunately I found out that routines are not yet supported on my Samsung watch 4. Google assistant reports: routines are currently not supported on this device 
I am waiting for Assistant to be rolled out on my Watch 4 in NL, but hearing that is a disappointment. I rely a lot on routines to fix awkward commands.
The reply is strange though. Instead of not recognising the starter and saying it doesn’t understand you, it blatantly says: I know it is a routine, but I’m still not going to do it.