My knime workspace is on a place that is also a DropBox folder with extended version history. In addition I use Backblaze again with extended version history and also Apple Time machine to an external drive if connected.
You can use this workflow to manually backup all other workflows in a folder to a designated target which might be a OneDrive folder holding the compressed files. I might add an option to exclude the data itself in order to save space.
OneDrive as a location for knime can have any sort of problems not the least with file names
You can read more here
@mwiegand gifted us with his version of a Backup system though I must admit I have not tried it yet (you can read more about this here).
In general I distill working concepts into sample workflows that work as they are and send them to the knime community hub so as to have them ready for me and other people as an additional form of backup.