To disable email order notifications to the administrator, but send them to customers:
  1. In the administration panel, go to Administration > Order statuses.
  2. On the opened page, click on the necessary order status to open the Editing status page.
  3. Disable the Notify orders department option.
  4. Click the Save button to apply the changes.
After that, no email notifications of the changed order status will be sent to the administrator.
NOTE: If the administrator continues to receive notifications, go to Administration > Storage > Clear cache to clear cache.