Does resetting the driver settings help by chance?
Morogoth has a good callout as well. For Nvidia, DSR is a very common cause of the cursor being misaligned. It’s in the 3D settings for under DSR - Factors and turning this off should help.
If it persists, try deleting the Variables.txt file in Documents/Heroes. It’ll be recreated once the game launches. This should help reset the resolution settings for the game if it stored some settings.