Hardware.Info posted ASRock Fatal1ty AB350 Gaming ITX/ac & X370 Gaming ITX/ac review: more AM4 ITX options A quote from the article:

A while ago we reviewed the first socket AM4 mini-ITX board that reached our test lab. ASRock is the second manufacturer with an ITX model for AMD Ryzen and they immediately sent us two boards: the Fatal1ty AB350 Gaming ITX/ac and X370 Gaming ITX/ac. Which one should you buy if you're building a small-size Ryzen build?

 ASRock Fatal1ty AB350 Gaming ITX/ac & X370 Gaming ITX/ac review: more AM4 ITX options @ Hardware.Info