The thing that I have noticed in his first two starts is that he is absolutely not scared. He trusts his stuff to the point where he feels like can challenge you, and even if you know what is coming, you aren't going to hit it.
We have seen it with guys like Lucas and Dylan Covey. They get into situations and they nibble and try to be perfect, and it amplifies the problem. Kopech just looks at the hitter and thinks F You, you can't hit me.