I know OneDrive can be set-up to sync files to a specific location on your workstation (I think Google Drive too), and then it keeps a copy there and keeps it in sync with the copy in the cloud.  Therefore, you could probably configure Laserfiche to store a volume in that location.  Office wouldn't be able to do anything with the volume file(s) but would sync them to the cloud.

However, I would be very worried about something going wrong with the sync process and causing the volume file to become corrupted - so I wouldn't recommend this.

If your goal is back-ups, there are going to be more efficient and accurate ways to do it.  If your goal is to remove the need for local storage, I would recommend looking in to Laserfiche Cloud.