Much like manually defined MQTT entities, one should be able to define the device to which a template entity belongs.
Here is an example of something that I just created:
mqtt:
climate:
- device:
identifiers: ["house.air_conditioner"]
name: Air Conditioner
manufacturer: Daikin Industries, Ltd.
model: FTXA35BS
name: Thermostat
... # Other configurations here
template:
- sensor:
- name: "Air Conditioner Current Temperature"
state: "{{ state_attr('climate.air_conditioner', 'current_temperature') }}"
unit_of_measurement: "°C"
device_class: "temperature"
# This is the feature request: the ability to set the entity's device.
# As of now, this will not work (do not try at home).
device:
identifiers: ["house.air_conditioner"]
This would allow for adding template entities to devices, grouping them all together.
The same syntax proposed for the MQTT integration could be used: