Graphite What I said was that Owner can't see it in "Install available apps" unless it is installed in Owner - which I and others prefer not to do even though it is probably safe - but I don't know exactly how it will behave. I know it's not visible because I tried it.
But this "install available apps" limitation is only a UX limitation because the pm (package manager) command can do this from the command line when Owner opens up ADB (debugging) and remotely executes "adb shell 'pm install-existing --user 0 com.example.app'" (so says another post).
That prompted me to look for a terminal emulator to do it locally. Hence my post.
If there were more doc available or clear discussion about it- and there may be but so far I haven't found it - I might be convinced to intall everything into Owner. I would prefer to err on the side of caution until I know better.
I can live without root access and Owner being a half-baked "admin" of sorts but when I am forced to log into Owner at boot then I start getting uncomfortable about installing apps there. Yes, I suppose you can install Google and immediately disable it but that's still bad practice. The Android model is deeply problematic in this regard. Being forced to look to untrusted third-party apps is not a good alternative. A sane solution would be to allow Owner to install apps directly into other user accounts.