The hardware seems to be the same on Elegance, Avantgarde, Sport, etc versions (sites like FCP Euro sell the same suspension parts for all versions).

So I'm guessing the difference is controlled by software.

And if it's just software, I'm wondering if it's possible for a dealership or independent mechanic with a STAR tool to re-program the height, stiffness, etc. to change from one suspension to another.

If possible, is this an easy or hard task?

I doubt theres any difference thats why u have airmatic u can change urself height etc with controls in the middle