No i mean the converters do exist, but on the msi gaming 5 if you are using the M2 slot the PCI-e 5 is disabled, so that wouldn't work i think.
this is what I was not sure about, if using m.2 disabled a PCIE lane or just some sata ports.
still might get one to try for the fun of it though

Anyone figure out how to get 8 GPUs on the MSI Gaming 5?
My power supply supports 9 PCIe power cables, be awesome If I could fit 2 more GPUs.