The motion sensor is a steering device, which means that it directly communicates with light bulbs. I think Homey’s Zigbee implementation cannot handle these devices (the same is true for the 5-button remote, which also isn’t supported; I don’t know what makes the rotating dimmer special, because that device is supported).
I read about a hack where someone paired the motion sensor with a bulb that had its LED’s removed (so it wouldn’t light up, but it would still update its on/off status to the controller; it was basically used as a proxy the communicate the state of the motion sensor).
