problem restoring legacy boot mode system image on to UEFI pc

Hi

I have a problem in that a system image backup was being created from a Windows 10 PC - using the built-in Windows system image feature - this system image was then being saved to a network location.

An old Dell PC suffered a hard disk failure and a new Dell PC was purchased to replace it. The old Dell PC used legacy mode bios while the new replacement Dell PC does not have a legacy mode bios at all and is UEFI only.

Restoring the image by booting-up to Troubleshoot > Advanced Options > System Image Recovery > (selecting the image file on the network)

but when trying to restore this image I get a system image restore failed error message - it says that the image was created on a BIOS computer and this computer is using UEFI (see attached).

I didn't create this mess, but none the less I am expected to sort the mess out as it as this computer performs a necessary task. As a temp fix to get around this problem, I took the m.2 drive from the new PC and fitted it in to the old PC with the dead drive.

Restoring to the old computer fitted with the new m.2 drive appeared to work - as I saw the "Windows is restoring your computer from the system image" progress screen, but on rebooting, I got a "inaccesible boot device" BSOD (see attached).

I feel the main thing is to get this old PC with the m.2 drive fitted working, after which I can worry about the new computer.

Any suggestions as to how to solve "inaccesible boot device" BSOD in this situation?

Thanks