I dont have this exact issue but something did come to my mind that may help.
Baby powder or some sort of body powder. They are pretty good at absorbing excess body moisture. Ive heard of long distance bikers putting it on their thighs to help reduce chaffing. And climbers use chalk powder on their hands to increase their grip.
Maybe try getting a small bottle of the stuff and lightly powdering your hands with it. Of course your hands are going to look powdery and some may come off on the controller if you use too much but once you learn how much to put on without getting it on the controller it would be nice. Or you can always wipe the controller down once you're done.
