Few know that Blender can also export Nurbs from OBJ files (curves) so it could also be useful to use this format while with x3d that also supports NURBS, is possible the import of nurbs surfaces edges.

In fact, if you also export something from FreeCAD to X3D or to wrl this is converted into Bézier Nurbs curves, attached an image with only the boundary of the shape as bézier curves

Import/export of curves between Blender & Plasticity or other software would be extremely helpful

That would be very neat trick.

This is a fantastic feature request!