On Hard to computer goes out of its way to hate you just for being human. If you want the AI to behave normally but have an advantage (besides Lucky Nations), you just have to turn up Advantage/bonus to AI. IIRC Hard does not give any direct bonuses except from making the world more inclined to hate you.
Hard doesn't make the AI hate you just for being human, it makes the AI
fear you just for being human. So they react more strongly to human expansion, put more resources into wars with humans, and will leap on an opportunity to attack a weak human that they want to conquer them/cut them down to size. It doesn't attack you just because you're human though, so you're not gonna start up the game and have everyone be hostile to you.