One of the biggest improvements of the Motif ES over the original Motif is the ability to have 8 Dual Insertion Effects active at once in a Song Mix or Pattern Mix. This means that you can have more PARTS sporting their Voice mode arsenal of processors. When you view the Effect screens: MIXING> EDIT> COMMON> F6 EDIT
You will see at SF2 INS SW. Here you can select which eight Parts will recall their Dual Insertion Effects from Voice mode, or you can apply them to the AD (analog-to-digital) Input. It defaults to the first 8 Parts. If you wish to reassign them you must turn them OFF on one of the first 8 and activate it on the PART you wish to recall it on.