How to add Alexa devices which are not supported with each App

Finally working!!!

So, for SonOff Dual R3 Wifi Model switch device the solution is found and working!

  1. Create an ambient in Ewe link app for your Sonoff switch device.
  2. Connect Ewe link app to Alexa
  3. Within Alexa app, create a routine based on the ambient created on first step.
  4. Connect Homey pro App to Alexa
  5. Within Homey Pro app using Alexa app you must add your Sonos speaker or echo speaker.
  6. Create a new workflow and on section, THEN you will have available trigger Alexa routine.

thanks, @Andy_Henderson !