I'm unaware if Acronis only has this issue when using a computer using GPT and imaging a MBR or if the same disaster applies when booting from an MBR machine.
If you're using a GPT boot method on the computer you're imaging from or windows 10 1803+? that you need to be mindful when initializing the disk to choose MBR boot method otherwise you will use the default boot method of the computer you are using. ATI in turn, uses that boot type when imaging. I found that when you initialize your drive in windows 10 it will initialize to the same Boot type that is installed on the machine your using or at least the new build of windows 10 forces GPT.
I was about 10 seconds away from finding a different Imaging solution when I realized this interesting factoid. With regards to your customers still running XP, then unless these computers are permanently offline, these represent significant risk to business, as will be the case for Windows 7 after Microsoft drop all support for it early next year. I use an Orico dock I got from Amazon that does this (no longer shown as available - but lots of alternatives). If this is a repetitive business requirement to clone drives, then I would suggest investing in a hardware dual-dock clone solution where you could put the source & target drives in the dock, independent of needing to connect to a computer then perform a bit-for-bit clone where the format of the drive is not important. After all, I can't possibly be the only one with customers who still run XP, and there's quite a few. I understand MBR is older … but there's still plenty of need for cloning software to handle it easily. The machine that has ATI 2019 on it … its not ideal to keep rebooting and changing modes in bios. In my work environment and market, I have the need to swap drives and clone on the fly via usb port.