(https://github.com/microsoft/promptflow/blob/main/src/promptflow/promptflow/__init__.py)
lines 9-27 include a try catch that masks the true ImportError

in our case this error was being masked requiring modification of this file locally to see true ImportError:
Azure/azure-sdk-for-python#44237

in our case this originated from line 19:
from promptflow._sdk._pf_client import PFClient as _PFClient