Ah didn't know it doesn't work on that mode. =\
It's really dumb and honestly may put me off playing it more.
It didn't tell me that the difficulty couldn't be changed when I selected it.
It doesn't feel fun to play. It feels like you need to cheese EVERYTHING because every fight is against enemies with 100+ health, 50 armor and 50 Magic resist.
I've been told that the Tactician mode in Divinity OS was actually quite good with changed encounters and the such. But in OS2 they simply gave a 50% buff to damage, health, armor, and magic resist and called it a day, which is crazy considering the OS1 tactical mode only increased everything by 25%.