Delta Drive, Delta Trust & My Drive · Linked folders and copies
How do I link any folder on my Mac to Delta Drive?
Short answer: Choose Add ▸ Link a folder…, pick a folder on your Mac, name it in your drive and choose online only, offline only, or both in sync. You can change the mode later without deleting anything.
Use a Link Folder: choose Add ▸ Link a folder…, the Link a folder… button on the Copies screen, or Link a folder… on the right-click menu of empty space. Pick any folder on this Mac, give it a name in your drive, and choose how it should be kept — Available online only, Available offline only, or Both, in sync.
You can change the mode at any time, and changing it never deletes anything on either side.
See the three modes and why a link can be refused.