One github repository to house multiple templates that may not be related.

[samueljoli]

In Nix land it's possible to have a repository that houses many templates that represents adhoc dev environments. You could have one that is based on languages, take for example https://github.com/the-nix-way/dev-templates, which has templates for a variety of different languages. Obviously this is great for creating a jump off point and does not take into consideration project evolution, and that's fine for this use case.

Would it be possible to do the same copier?

[pawamoy]

If you don't care about project evolution, sure, you could use a templated _subproject value (that depends on an answer to select the template).