Hello
Xiaomi a safe bet, I am equipped with a Hub, various sensors
Echo plus V2> Skill Yeelight
In application on IPhone, Mi Home, Yeelight
Attention to the configuration of the servers:
On Mi Home to have the extent of the material potential … I am on the Chinese server
that’s where it stings so that Alexa detects the bulbs Yeelight must be connected with the Yeelight app to the German server
So we have to choose between Mi Home or Alexa, not obvious without Mi Home more interactivity with sensors … via light bulbs 
Do you have a solution ?
Thank you