I have a Huawei Matebook with the Ryzen 5 2500U atm and I have had some issues, but I resolved them by using the beta version of the distro I wanted. I think they support might not be 100% there yet but it’s coming soon from my experience. I haven’t had time to properly install it but I have tested a live usb so far.
I know you will but please report back with a detailed rundown under Linux. I am also in the market soon and would like something that plays well with Linux and some native/ home streaming performance also.
By November kernel 4.19 will be good to go.
If you aren’t using an APU you don’t need 4.19 though.
Either way when the laptop arrives, depending on the distro you might need to turn modeset off just to install it, then after you install the new kernel you can boot normally.
Once the October distros come out that may not longer be needed.