“What is the best face wash for cystic acne?”

No face wash will be adequate

Salicylic wash, glycolic wash.

Best facial cleanser for acne, in general, is one called AsepticMD that I was involved in developing. It has a completely unique ingredient called Dioxicare that supports the natural balance of skin bacteria and exfoliates at the same time, in a completely non-irritating way. I recommend the Foaming Facial Cleanser. It isn't marketed but if you google it you'll find it.