I forgot this to post:
- platform: template
sensors:
temp_aussen_template:
friendly_name: "Außentemperatur"
unit_of_measurement: "°C"
value_template: "{{ states('sensor.aqara_tempsensor_aussen') }}"
This unfortunately do not appear in GH
All the docs for google assistant via cloud or the smarthome skill are located here. But it turns out that Google Assistant doesn’t have the display_catagories like alexa has, so that’s not an option. You’re only option is the template sensor.
You’ll notice that temperature sensors will transfer.
Use the following config and it should transfer:
- platform: template
sensors:
temp_aussen_template:
friendly_name: Außentemperatur
unit_of_measurement: °C
value_template: "{{ states('sensor.aqara_tempsensor_aussen') }}"
device_class: temperature
But you already have a temperature sensor, sensor.aqara_tempsensor_aussen so the template sensor shouldn’t even be needed, just customize that sensor.aqara_tempsensor_aussen entity with device_class: temperature.
Thanks for your answer. I put it in my config and the device popped up in GH. Unfortunately the response is still
“Außentemperatur is OFF and it is 13°”
I just want to get rid of this OFF statement.
Are you asking the correct sensor the question? Seems like you’re still asking about the thermostat. You have to ask the temperature sensor. You should probably rename the thermostat to have thermostat in the name.
Yes I am sure it is the right one. I renamed it meanwhile to “BLA” to be sure it is the right one.
After renaming to “BLA” the response is:
“BLA is OFF and it is 13° ”
Then there’s not much you can do. That’s all handled by Google home. All home assistant does is present the sensor to google home, google home comes up with the response. Maybe you should start asking this question on google home forums about temperature sensors.
Well, with Google it is such a thing… In my experience, they only do what they want and are not really interested in other ideas…
If it would be possible to template the target_temp it would be perfect from my point of view. Due to the fact that this isn’t possible, I followed the suggestion of @tom_l. I have created an automation that updates the target temperature of Außentemperatur with every change of the measured temp of Außentemperatur.
Workaround solution is as followed:
Device:
climate:
- platform: generic_thermostat
name: Außentemperatur
heater: input_boolean.dummy_thermostatschaler
target_sensor: sensor.aqara_tempsensor_aussen
initial_hvac_mode: heat
Automation:
alias: Sync Außensensor (WORKAROUND)
description: ''
trigger:
- platform: state
entity_id: sensor.aqara_tempsensor_aussen
condition: []
action:
- service: climate.set_temperature
target:
entity_id: climate.temperatur_aussen
data:
temperature: '{{ states(''sensor.aqara_tempsensor_aussen'') }}'
mode: single
It works. So I will go this way for now 
Turns out google home doesn’t support temperature sensors, so home assistant exposes them as climate devices.
So what’s the exact state of the climate device when you just get a phrase for the temperature as a response?
You have gone to a lot of trouble instead of just doing this:
petro:
Are you asking the correct sensor the question? Seems like you’re still asking about the thermostat. You have to ask the temperature sensor. You should probably rename the thermostat to have thermostat in the name.
Maybe I am misunderstanding “trouble” in this regard , but it was not my intention to cause trouble… Sorry for that!
EDIT Hmm… now the post of @tom_l is gone? 
It is like this:
Mode is “heading” and both temperatures are identical.
And yes it is an thermostat, what is okay for me as long as the response is just the temperature. I use google 99% by voice, its UI is secondary. As primary UI I am using HA.
I deleted it because it was based on incorrect information.
Seems to be so
However for me the problem is solved. Thanks for the support!
