@DigiH I just wanted to thank you for your help, I have built another OMG RF device based on ESP8266 (D1 mini) and STX/SRX882. I have tested it on a set of ZAP RF 433 power plugs and all seems to be working fine.
I did not really understand how to make it work, I opened an MQTT Explorer client session with the OMG RF gateway being discovered and integrated in HA. I then used the remote control from the sockets to send ON / OFF signal. I captured the value in the MQTT Explorer client (you can also capture it from HA) and created an HA MQTT-based automation to send the ON / OFF value.
Next step is to check how to integrate my PIR sensors, I guess there’s value sent when motion is detected and another one when motion is no longer detected…I will investigate on it.
Again, thanks a lot for your help!