instamat has a bunch of geometry processing stuff and the way it handles presets for painting etc is very nice. so there's a couple of plus points over designer however it has a very, very long way to go to become a serious option as a replacement for designer mainly cos the ui is pretty obnoxious and the library…
Designer is probably the way to go. But I did find this artstation post that may help:https://www.artstation.com/blogs/saschahenrichs/9vGl/ndo-photoshop-script-v0666-from-quixel-to-create-normal-maps-in-photoshop