[2021] Mouse offset with scaling software (Borderless gaming & Windowed Borderless Gaming)

I can't think of a solution for your unusual situation are requirements, i"m sorry. Windowed mode will allow you to put it where you want but you'll have to reduce the resolution slightly to fit in the screen.

Supported resolutions are listed at the end of the file Documents/Paradox Interactive/EU4/logs/system.log