Is it possible to use a third party speaker only as tts and stt service?

For example, when I say “Hey Google, turn on all lights”. I don’t want it to execute it. I want the Google speaker, convert the voice into text, then send it to Home Assistant. Next, the text command will be executed on the Home Assistant side, and the text result will be sent to the Google speaker, which will be converted into voice and played.

Why?

No need to put these steps in place as it will have no advantage over just using google to execute the commands on HA.

What do you mean by this?

Just follow this and google can operate anything setup in HA.

Gotcha. Thanks! I will dive into it.