You can either move a whole folder to you other disk and link it back to your original location with soft links, or move the files and make hard links for all of them.
The windows command for doing this is
mklink. It's like creating shortcuts to files in other locations/drives.
I've only tested creating soft links (I moved index folders from HDD to SDD for speed) and I can confirm it works. I think hard links should work as well.
In your case, moving the folders wouldn't solve your issue, since the data would still be on only one drive. So the solution would be to move the large files to your "empty" disk and make hard links for all those files.