I’m sorry but that incorrect.

Ribbon, Assignable Sliders, Knobs, Expression…. They are all fully assignable on any KORG and can be mapped to most elements of a PROG sound. KORG also supports the exact same number reversal ability you mentioned if you for example want to control the AMP or a filter.

Your very own OASYS even far exceeds all that with the Vector Joystick. In Prog Mode you can cross fade between layers and assign midi CC values like CC07 or 13 to the Y and X directions and so on.

Jump to COMBI mode and you can then have 16 different PROG sounds assigned, each with it’s own individual Vector setting, and even a master vector layer over that which you turn on and off for each individual track in the COMBI.

Even a Pa1X has a 16 part prog that can be programmed to respond to sliders and external controllers.

Regards
James.