You mentioned it as being a critical feature but from what I've been reading, it's pretty complex and tricky due to it's weird syncing rules and relationship with OneDrive. The only decent solution requires a Windows version. See: https://answers.microsoft.com/en-us/msoffice/forum/all/good-...
Dropbox. Basically, you can create a new notebook and all pages under that notebook are organized in a directory hierarchy. I've done this for just under a decade without issue.
You are able to print entire notebooks as a pdf. Its not the best, as text can be cut across pages if you don't originally fit into nice-paper sized areas, but it does export everything quit easily.
https://support.office.com/en-us/article/export-and-import-o...