I think you're misunderstanding something.
Miracast is a GRAPHIC CARD standard. Not a CPU. Ryzen or CoreI cpus have nothing to do with Miracast. FYI both AMD and INTEL iGPUs on their cpus supposedly support Miracast. Miracast requires a display adapter which supports Windows Display Driver Model (WDDM) 1.3 which to the best of my knowledge includes all current AMD and NVIDIA GPUs, it also requires and a Wi-Fi adapter that supports Wi-Fi Direct;
Just be careful about your WIFI adapter and you should be able to make it work.
THAT SAID -
from a little research I've noticed while NVIDIA claims support for WDDM 1.3 and Miracast, it turns out nvidia actually cut support for Miracast back in 2016; meaning you'd need some of their older drivers and a card available in 2016 to make it work. Furthermore AMD graphic drivers seem to be hit and miss. I see a number of their APU listed as having drivers supporting Miracast and a smattering of their GPUs, but it's all over the place. Looks like AMD is working on their own miracast like product hence the lack of dependable support.
Looks like you'll have a more likely chance to make Miracast work on a laptop then you will on a desktop; but yes, windows 10 supports miracast.