shivamjha I am very sensitive to pwm and these are the monitors I had 0 problem with:
Asus pg35vq, Asus pg348q, Dell u3415w, Acer predator x35, Alienware aw3418dw, BenQ gw2780
All of them are flicker free and have very low nits at 0 brightness setting, I control the brightness only with the contrast setting.