june (she/her)

Its only “Navigation” apps though, media and messaging apps work just fine in Android Auto from another source or sideloaded.

I’m not sure what exactly the previous commenter said but map apps in particular only show up if installed through the Play Store. I found that out after trying to get Organic Maps working through F-Droid and Aurora Store. If you’re rooted you can change the app’s ‘installed from’ field to the Play Store and it will show up.