Modify parameters of grubnetx64.efi

I need to customize the grub.cfg path embed in prefix parameter of grubnetx64.efi file which I downloaded from here GRUBNETX64.EFI. I need this for my network boot environment(PXE) setup.

I used this file to boot winpe and it works fine with the default directory which is grub/grub.cfg. When I run set command in grub menu at network boot, I can see prefix=(tftp, 192.168.1.254)/grub.

What I need is prefix=(tftp, 192.168.1.254)/grub-efi-xyz

How is this grubnetx64.efi built?

When I built my own grubnetx64.efi with grub-mkimage command, after network boot with winpe, throws BLInitializeLibrary error 0x0000001 but not with official grubnetx64.efi image.

I need the build steps for official grubnetx64.efi file.

Thanks!