I got the answer from a member of Audiofanzine forum.
To vary different parameters simultaneously with the expression pedal, we have to assign a CC (72 for example) on the RCV CTL menu. "Pedal" was added on the update, so it doesn't exist in the manual. Eventide should update the manual.
For each preset, we have to set the min and max value of the desired parameters with the expression pedal, and finally save the preset.
So this the way to vary different parameters simultaneously with the expression pedal, but to vary one parameter at a time, I will continue to use one CC / parameter (CC0 for KBO, CC1 for KB1, …). It's easier and faster.
