You'll have much better chances if you can just buy external GPU since there are laptops with working IOMMU and there are people who got external GPU working in

You'll have much better chances if you can just buy external GPU since there are laptops with working IOMMU and there are people who got external GPU working in VM. Then for macOS it's going to be just normal PCI(e) device. Unfortunately (almost?) all mobile GPUs won't even initialize within VM. I'm not expert in hardware side of things, but I suppose laptop drivers expect specific topology since mobile GPU almost never have own connection to display and sometimes don't even have own ROM. Even if somebody will find a way to make passed mobile GPU work on Windows VM it's very unlikely same trick will just work for macOS.