I asked if this is possible here: https://answers.unrealengine.com/que...thout-inc.html
I got some useful replies but I learned that it's not.

There's a folder with starter content in the UE4 installation location (under samples) and I'd like for us to be able to browse it in the content browser the same way we can browse the engine content.
It would be a lot more efficient than UE4 creating a 600+ MB duplicate of that folder for every small project you create.