We are using 2016 On Prem
For our site collection an admin user can do the following
- Create Sub Sites
- Create Document Libraries
For any of these items we use custom content types to enforce metadata that is required to be filled in before they can check in anything
What we would like to do only change the content type for them every time they create a new library or a list without any full trust code
Something like Hub Content Types, however in classic mode on 2016 On Prem