Well I may be misunderstanding your direction but with the Dura Ace 9070 I can program any of the buttons to control up/dwn front or rear. I just went into the system to confirm but if I want the left shifter outer button to control front derailleur up and inner left button to do rear derailleur up then no problem.

On the multishift that is done as a complete set-up and not per button but frankly it's faster to tap the buttons per shift vs. the high speed multishift mode. In my case I have it programmed to keep the multishift so I can use it when I want.