Are they an exclusive feature of Nabu Casa HASS Cloud?
I integrated Alexa and Google Assistant manually with my own server/domain and is currently working.
But they’re not showing in the Voice Assistant window for setting “Expose” and “Alias”.
I guess, if that’s disabled for you, Google Assistant is not correctly tied to your instance. IIRC, to get HA to expose its own entities to Google, you indeed need a Nabu Casa subscription, as they somewhat need to bridge these services for you through their cloud.