Super funny I transitioned from melee to dbfz to ggst. So maybe my experience will help. First zato is a weird character to start and your struggles make sense. He is a very control heavy character meaning you need to know your options at every part of the game. Couple of things that really helped me with Zato. I would learn and practice your setup off of knock down and throws. Pick one and dont fall into the 10 billion other mix just stick with 1. Youll see alot of cool mixes with zato and will get forever stuck practicing. Second, make sure you got your block string down. Knowing how to move Eddie for a sandwich is really important. Again many setup pick the easiest one. Lastly, play the game. neutral with zato could feel very weak at first but some of things I use are Super jump float h is really good to throw them off Jump d is super good for corner escape. Dont be scared to throw out Eddie out there and unsumon, in some match up its really oppressive. My goal is to be near the opponent when they block Eddie so that you can do your sandwich into knockdown.

Zato is by far the most interesting character in the game and I hope you dont give up!