@laurent_aodyo I would love to hear the latest on the prospects for a key bend. Bending notes is central to the physical flutes that I play (open-holed Native American flutes) and the absence is keenly missed. Like @gobarcza, I keep turning it on once in a while and then abandoning key bend an hour later.
The issues are easy to state, but I cannot imagine a strategy or programmatic method or simulate an authentic physical-world key bend:
Knowledge of what note is being bent to (the target note) so that the appropriate span of bend (1x semitone, 2x semitones, 3x ...) to select.
The avoidance of a noticeable discontinuity - a jump - in pitch when near the target note.
The lack of a sensitivity setting for key bending to avoid accidental activation.
If there is anything I can offer in the way of assistance (Guinea pig, beta tester, human sacrifice) I would be happy to sign up (uh ... maybe not the last item).
Another option might be to (optionally) generate the key bend data as a CC and allow a downstream rendering engine attempt to produce key bends. Such experiments could be done directly in Kontakt or even a VST ...