Check out Shelter. Iuse Shelter myself but I have heard that Insular does the same thing. Shelter has an option of installing from APK directly into work profile. I tried installing different versions just now and it worked.
Edit: Hadn't properly read your post. Changed my reply to better fit the question
What is the root scene on Graphene? I know the dev is pretty against it but I like having root access after being used to it. Is it possible to easily root it without any integrity issues later on?
tar --help
is a valid command :p