I've follow this tutorial https://kb.amd-osx.com/guides/MJ/ryzen-native-usb.html
I've succeed to follow it until the copy of the installer files and the command lines that should be done after it.
But now, I can't reboot and my HDD, at the end I have the graphic interface of macOS that says me "The installer resources were not found" and I cannot do anything else than restart.
The last lines were like this (he repeat the 2 last lines 3 or 4 time) before the error message
In the config.plist I'm sure there is too much things activate but without this one (if I try to make my own and without patches) I can't boot on the USB key.
An other problem that I think it could help is SATA Warning : Enable drive PHY PM failed
16 Go DDR4 3000MHz
ASUS Prime X470-PRO
MSI RX480 4Go