In Cubase 7.5 it seems to work… Devices/VST connections/Add FX/quadro configuration/add child bus to FX-“stereo”/add child bus to FX-“stereo (Ls Rs)”. Insert EQuivocate on the FX bus and there we have the two inputs, “stereo”, and “stereo (Ls Rs)” as sidechain. But I’m new to the process, so might be wrong…