1.I contacted Mirrorlink expert via e-mail and got a full guide to resolve the problem on Subaru Outback 2016 (using Samsung Galaxy S9).

Few things to have it fully working on Subaru:

1) Be sure that your car HIJ Mirrorlink is updated from1.0 to 1.1 (you can ask Subaru dealer to do it, it's 30 minutes procedure.

2) Install Audioteka certified app from Google Play (RockScout doesnt work on Subaru.

3) UNINSTALL Samsung CarMode app. It blocks connecting. I dont know why Mirrorlink is greyed on HU if carmode is installed.

4) Clear all caches of Mirrorlink app.

5) Configure floating apps for your own needs(enable "Subaru mode" and configure launcher)

6)Connect and enjoy!