I have the SLZB06 - It's brilliant and allows me to place the coordinator where you want it. There are others, when I researched, this was the most professionally produced. On any one Zigbee setup, you can only have one coordinator, however you can have two Z2M instances which just have different names referenced in MQTT..... Just becareful of band overlap choices (source: https://www.facebook.com/groups/HomeAssistant/permalink/3698083280463015/)