TL:DR don't remember which Thermostat you're using. I don't own a Zwave Thermo so I can't migrate one to ST.
What I did do is find a horrible example of a Virtual Thermostat and installed that into ST.
From the IDE, it says it has:
temperature: 20 °C
heatingSetpoint: 23 °C
thermostatSetpoint: 23 °C
thermostatMode: heat
thermostatOperatingState: off
After making sure that I can change the temp on the ST App, I added it to HubConnect and the device correctly appeared under Devices. I clicked Sync on Hubitat's Device Info page for it and about One ST Delay later I got:
Current States
coolingSetpoint : null
thermostatMode : heat
thermostatOperatingState : off
heatingSetpoint : 23
temperature : 20
schedule : null
supportedThermostatModes : null
supportedThermostatFanModes : null
thermostatFanMode : null
thermostatSetpoint : 23
So, while the standard Hubitat Thermo offers more attributes, this horrid Virtual driver does populate the 5 it knows about.
On ST's App, I tapped the slider to be 17 (its in C) and the mirrored device now reads:
Current States
coolingSetpoint : null
thermostatMode : heat
thermostatOperatingState : off
heatingSetpoint : 17
temperature : 20
schedule : null
supportedThermostatModes : null
supportedThermostatFanModes : null
thermostatFanMode : null
thermostatSetpoint : 17
At this moment, my test is NOT to find a superb Virtual driver and test 20 attributes. This is the test a few steps before that.. in which I verify what I expect to happen, does happen. To say it another way, the attribute:value pairs are sent as encoded text, and thus what letters make up the pair is less important (at this stage) than they do, in fact, get sent.
I then, on 'coordinator,' set the Heating Setpoint to 28 and as if by magic, the ST App shows 28
Received event from ZeeSmarts/TestSTthermo: [thermostatSetpoint, 28 °C, isStateChange: true]
ST IDE:
temperature: 20 °C
heatingSetpoint: 28 °C
thermostatSetpoint: 28 °C
thermostatMode: heat
thermostatOperatingState: off