what I hear is, you want to set up a production instance on a rolling distribution, using the primary tool installed on PY2 and the actual frappe environment on untested PY3.8
why?
From the screenshot (and the ModuleNotFoundError) what I can infer is that erpnext isn’t installed in your bench’s virtual env. Perhaps try installing it again on your bench; either via bench get-app or bench pip or just manually by accessing the env pip.