how to make boot drive usb mount/boot windows nvme (different drive) ?

I have a usb stick booting with grub that boots a linux kernel and mounts root nvme p1 partition (linux). EFI and /boot/ folder resides on that stick (sda1) . How can i have my stick chainload boot windows (nvme partition 2) ? Is there an EFI nvme driver? Again, bootloader is grub2

usb drive: sda1 (contains grub files /EFI/ and /boot/).
p1 (linux)
p2 (win)

i don’t know much about grub2 but perhaps the clover bootloader option can offer some hints as it specifically calls the NvmExpressDxe -driver i have read else where that a similar idea can be done with grub2 so i assume a driver for it exists somewhere.

[Guide] NVMe-boot without modding your UEFI/BIOS (Clover-EFI bootloader method)