This is an experimental feature, ongoing discussion can be found here:

When report is enabled, devices will report their state changes to zigbee2mqtt even when the change is not directly done by zigbee2mqtt. This is especially handy when the state of a bulb is changed by e.g. a remote or via groups.

To enable report, add the following to your configuration.yaml:

  report: true

Zigbee2mqtt will discover devices which are eligible for reporting. The zigbee2mqtt logs shows for which devices report is configured.