There’s a way to do this with an iGPU/dGPU pair. Essentially it means firing up the VM with dedicated GPU passthrough, and then remoting directly into it from the native install using something like Parsec; but if I recall there was a direct memory access way to get the passthrough GPU output to the main display as well; I just can’t remember it at the moment.
The alternative is having a monitor with dual/tri inputs, and swapping the output to the dedicated GPU. Maybe some trickery with a KVM to move the mouse/keyboard over.
looking-glass.io – This may be the other solution I was having trouble remembering.
Using something like “Barrier/Synergy” might be a software-solution for the KVM side of things. Some guys also just opt to have their dedicated GPU hooked up to a second, dedicated monitor.
edit Reading more into this, I missed the part where this was a laptop - you’re likely hosed. Laptop dedicated GPUs also run through the internal GPU; so technically you have 2 GPUs in your system - but from what I understand, they basically have dedicated switching hardware for handling the handoff, and I’m not sure modern laptops allow any such control over all of that.