Yes, the mixing and matching offers a few possibilities. Users have available violin(s) in combinations of 1, 6, 14, and 20. The "ones," of course, can be stacked for 2 or 3 (though sometimes phasing can be an issue).
With violas, the choices are 1, 4, 10, and 14 instrument(s).
Cellos are alotted as 1, 3, 8, and 12 instrument(s).
Basses come in sizes of 1, 2, 6 and 10 instrument(s).
So with all this available. divisi can be done. I have wondered if VSL will, with some new software, render an automatically dividing sound depending on the number of keys played, and perhaps add the sound of two or three violins to this end.