I guess we could check if somebody could pull the bios: Guide about how to check PCI-E Bifurcation support of any mainboard : r/Amd (reddit.com)I don't think that the CPU plays any role in this. In specific a CPU has a number of lanes and the chipset via the motherboard is the one that gives what is what in its connectors & slots. So from my understanding the x8 can be devide to 4x4 at least.
It's a decision from minisforum if they will implement this in a feature bios IMO.