I got one of these a couple of weeks ago. I could add it to my Matter/Thread network running on Home Assistant with a GL-S20 OTBR without any problem. In fact, so far it is the device that managed the onboarding procedure the fastest and without any glitch 
The Home Assistant device card (attached) is complete. The LED has the possibility to adjust color and intensity independently, and thus it will be really easy to create automations that can use it to show the state of the plug itself or of any other device in the Home Assistant ecosystem.
Of course, one can easily turn on and off the plug, read the real-time voltage, power and current measurements, and also the cumulative energy, as one would expect from such a smart plug.
The device has been working great, with accurate measurements and solid thread connectivity.
