How to sync or use an archive Mac Photos library on Onedrive?

We have scanned photos and videos going back to 1965, giving a library that is too large to be the system Photos library.  We therefore have a smaller system library on iCloud for current photos, and store our older photos in a separate archive Photos library.

We discovered quickly that iCloud will not accept another Photos library, so that we could not share the archive photos between machines.

Recently we found that our Office 365 subscription entitled us to 1tb of Onedrive storage. 

However, we now find that Photos will not open a photos library located in the  Onedrive folder and says you must move it to another folder.

But if you need to move a large library out of Onedrive, to look at or modify, and put it back, it will presumably take an age to resync.  We could fragment the archive library on Onedrive into individual years.  However, there won’t be space on the hard drive for both complete and fragmented copies of the archive library.

Question 1.  Is there a way of getting Photos to open and modify a Photos library on Onedrive?

Question 2.  Is there an alternative cloud storage package which Photos will treat as a normal folder?

Or is the only solution to put the archive library on a hard disk and take the hard disk to each other computer?