Zigbee Thermostate with external temperature sensor

I want to install about 10 Zigbee Smart Thermostates in my home, which I want to control using an external temperature sensor.

I bought an Eurotronics Spirit Zigbee for now, as it was listed as supported.

From searching through this bugtracker, I found out, that it is not possible to set the valve position of the Spirit Zigbee manually,
instead it is recommended to set the offset attribute every 30 minutes.

However, setting that attribute seems to have no effect. After executing a PUT request to /config with {"offset": 2} seemingly no clusters changed in the Deconz GUI.

Also, setting the valve manually if adjusting the TRV to Unknown 2 does work via the Deconz GUI, but it doesn’t seem to be exposed via API.

For now, I just bought one device, and I am wondering, what kind of device do you recommend for usage with an external temperature sensor? Is there any device which allows the valve to be controlled manually via REST API (Home Assistant) or which supports externalsensortemp and externalwindowopen?

If you can recommend me any device, then I will gladly switch from the Eurotronics to that one. The “Supported Devices” page doesn’t seem to be of much help as it seems to be incomplete and doesn’t list all the quirks and supported/unsupported attributes.