What about the opposite case? I have several python packages with one requirements.txt each. But for development I want to have a single “root” virtual env?
At this point I would say no, but work is in progress to improve in this respect [1].
At my place of work we use some rules [2] to build virtual envs from Bazel dependencies. It's been a great stop-gap for us and allows us to use traditional Python tooling (e.g. PyCharm) with Bazel-managed dependences.