[Answered ]-Django Python: Install multiple versions of the same package within a virtualenv

This is not possible with the usual python tools, since virtualenv are supposed to be used for that.

One possibility is to put each version of the dependancy in each app directory, this way they may import this one first instead of the other.

But if your goal is to not edit any of the apps code, you better prey they don’t play with the Python Path, nor share any imports related to the dependancies.