Java VM Options: Set a -Djava.library.path relative to project folder
You actually can set a relative path. For example if you start your program a specific folder, you can access libraries in a folder "libs" right next to it by setting the path to "../libs" e.g.
In my own project with native libraries I have this in my shell script:
-Djava.library.path=../../native/unix
Hope this answers your question.