I’m tempted to buy the following and wonder if you think I could get them working together with Home Assistant - I have no prior knowledge of Zigbee or Z wave
Xiaomi Gateway
multiple Xiaomi Gateway door sensors
Xiaomi Zeelights (already have) Sonoff relays for outdoor circuits (lighting)
Ring video doorbell (already have)
Check the component section on the website. There are components for all these devices so yes they will work ‘out of the box’ (unless you really have Zeelights… )
At first I thought you found an advanced version of the Yeelight
Sonoff is Wifi as far as I know so it will not connect to the Xiaomi gateway. The Xiaomi gateway and sensors are Zigbee but as far as I know the sensors do not work as repeaters, not like the hue lights for example. All the sensors are directly connected to the gateway.
That’s correct. Sensors that are battery powered (normally) do not act as a repeater - to save energy. Wired sensors act as a repeater and create a mesh network. Same with ZWave.