Synchronize States Between Two Lights

light-state-sync.yaml

blueprint:
  name: Synchronize brightness states
  description: Synchronize the on/off state of 2 entities
  domain: automation
  input:
    entity_1:
      name: First entity
      selector:
        entity: {}
    entity_2:
      name: Second entity
      selector:
        entity: {}
  source_url: https://gist.github.com/cdchris12/b3c3546bf446c265adb681088b2623e5
mode: restart
max_exceeded: silent
variables:
  entity_1: !input entity_1
  entity_2: !input entity_2
trigger:
- platform: state
  entity_id: !input entity_1
- platform: state
  entity_id: !input entity_1
  attribute: brightness
  
- platform: state
  entity_id: !input entity_2
- platform: state
  entity_id: !input entity_2
  attribute: brightness
condition: []
action:
- choose:
    - conditions:
        condition: template
        value_template: "{{ is_state(trigger.to_state.entity_id, 'on') }}"
      sequence:
        - service: light.turn_on
          data:
            entity_id: '{% if trigger.from_state.entity_id == entity_1 %} {{ entity_2 }} {% else %} {{ entity_1 }} {% endif %}'
        - service: light.turn_on
          data:
            brightness: '{{ state_attr(trigger.to_state.entity_id, "brightness") }}'
            entity_id: '{% if trigger.from_state.entity_id == entity_1 %} {{ entity_2 }} {% else %} {{ entity_1 }} {% endif %}'
    - conditions:
        condition: template
        value_template: "{{ is_state(trigger.to_state.entity_id, 'off') }}"
      sequence:
        - service: light.turn_off
          data:
            entity_id: '{% if trigger.from_state.entity_id == entity_1 %} {{ entity_2 }} {% else %} {{ entity_1 }} {% endif %}'
  default:
  - service: light.turn_on
    target:
      entity_id: '{% if trigger.from_state.entity_id == entity_1 %} {{ entity_2 }} {% else %} {{ entity_1 }} {% endif %}'