I usually don't move notes to and from OneNote. I tried this Obsydian importer, and it is OK for my meeting notes in terms of formatting. However, it has a bug that strips slashes from page titles, which is a bit of an issue for me because I always add dates to titles (e.g., 7/13/2024).
With a few good examples, maybe some LLM could help you with reformatting?
I have a similar system to you, but getting things in and out of OneNote is such a massive pain.
Everything I have tried requires significant reformatting (even Word).