ha_one_trigger.yaml

blueprint:
  name: Generic trigger template (one trigger)
  description: Turn one or more devices on/off based on a trigger
  domain: automation
  input:
    trigger_device:
      name: Trigger
      description: The trigger that will alter the state of the devices.
      selector:
        entity:
    target_device:
      name: Devices
      description: The devices to keep in sync.
      selector:
        target:

trigger:
  - platform: state
    entity_id: !input trigger_device

action:
  - service: >
      {% if trigger.to_state.state == "on" %}
        homeassistant.turn_on
      {% else %}
        homeassistant.turn_off
      {% endif %}
    target: !input target_device