Hello,
I bought the Lidl HG06106C Livarno Lux E27 bulb RGB…and I think I found an easier way to control it with the Zigbee2MQTT.
In MQTT Command Topic, we have to indicate the path zigbee2mqtt/FRIENDLY_NAME/set/color. Then if we choose CIE mode xyY (x, y, Brightness), in the Outgoing Value Format we have to put {“x”:%s, “y”:%s}. If we choose RGB mode (Red, Green, Blue) we have to put {“rgb”:“%s,%s,%s”} or {“r”:%s,“g”:%s,"b ":%s}.