I’ve successfully imported a number of OneNote notebooks from my Microsoft Work account but had to work around the limitation of Obsidian Importer which only supports importing from a Microsoft Personal account (live.com).
After much experimenting I simply recreated the notebooks on live and copied data from the notebooks on Azure, section by section, using the OneNote desktop 2016 client.
After doing that I found a note on GitHub from @swengalster here who suggested another workaround which may work?
BTW the Importer does an excellent job of importing from OneNote. I am impressed with the outcome