@jquartel you can change the directory used to store projects with the JVM argument
-Drefine.data_dir
On mac this can be modified in the info.plist file (see Running OpenRefine | OpenRefine)
A few years back I ran OpenRefine in the way you describe with a synchronised project directory between a laptop and desktop (I changed the directory used by OR using the JVM argument rather than linking the default directory). I don't remember all the details now, but my recollection is that it generally worked well, and allowed me to easily work across two computers. I have a feeling that I did occasionally have issues with the file sync from one computer conflicting with the file sync from the other leading me to get an older version of the project synchronised - so I definitely would agree about not having the projects open on both machines at the same time and I think your concern this could lead to problems is justified. I don't know how this works for OneDrive but with Dropbox it was possible to revert files in a folder to a previous point in their history so this offered some protection against files in the workspace directory getting overwritten by the sync.
I stopped this practice when I moved to just using a laptop again rather than laptop+desktop - so my motiviation to stop doing it wasn't driven by any particular issues with the approach but rather just my need to have this setup went away.
So my (vaguely recalled!) experience is that this setup can work but with some care! Its not a wholehearted recommendation - clearly OR isn't designed with this particular setup in mind - but it's a "it seemed to mainly work for me for a couple of years" 