We own a 2021 Subaru Forester and it includes the STARLINK remote start.  Throughout our home we have a number of smart devices, Amazon, Google and Home Assistant.  

I wanted to figure out a way to allow me to remote start our car without the need to use the Subaru app.  I discovered that Home Assistant ( https://www.home-assistant.io/) had an integration to Subaru, however it was only to pull data.  Then I discovered that someone else created a STARLINK integration – which supports remote start!  (https://github.com/G-Two/homeassistant-subaru)

I successfully configured the integration and was able to create an Automation that allowed me to call the subaru.remote_start service with the payload being vin:MY_VIN.  I created a webhook trigger so I can call it from other services, such as Alexa or Garmin.

 I configured the APICall widget (https://apps.garmin.com/en-US/apps/ac9a81ab-a52d-41b3-8c14-940a9de37544) for Garmin to allow me to trigger the web service and start the Forester.  I also created a stop vehicle one to shut it down if needed.

Please let me know if you have any questions!