Is there a way to play Spotify truly "everywhere"?

I have been using Home Assistant to play Spotify “everywhere” which includes all of my Alexa devices. The devices where it doesn’t automatically play are:

  1. Ecobee4 Smart Thermostat (w/ Spotify connect)
  2. Chromecasts
  3. Google Home

Is there any way to get Spotify ‘everywhere’ playing on any of these devices while also playing across all Alexa devices? I guess this is more of a Spotify-specific request, but wondering if there is a script that can be done to utilize this in HA.

Thank you