pert:
Yes, as long as you put a symbolic link or junction directory to that folder in {sketchbook folder}/libraries.I'm not necessarily recommending that everyone do this. It's just the only possible workaround I can think of that allows what wolfrose wants to do.
I would prefer if the Arduino IDE would support subfolders in the libraries folder. In my libraries folder, I have custom libraries I wrote and need to be careful not to delete, I have libraries that are dependencies of my projects which I want to avoid deleting so I don't need to install them again, and I have dozens of random libraries that I installed to use one time when providing support here on the forum. It is a lot of work to delete the unwanted libraries from my libraries folder without deleting the libraries I want to keep. If I could put the libraries I want to keep in separate folders, this task would be simple.
I got it, thanks.