Anyone here having VA ultrawide monitor ? im wondering if you experienced any problems with black smearing/ghosting ?
I would think that depends on the monitor more than the game/software. I would check reviews from different sources which compare monitors, eg Rtings.
AOC CU34G2X, rating 7,5 on RTINGS and its decently rated on Tomshardware,but still if it has visible ghosting ill pass on it.Couldnt find anything related to wow with this monitor
It says right there on RTINGS:
CONS
- Noticeable black smearing with fast-moving objects.
so i guess the display is just garbage for gaming and you should return or sell it 
How you can market something like that as a gaming monitor is beyond me.
I have two VA monitors and they are fine, AOC Q27G3XMN/BK 1440p and older LG 3440x1440. Better quality panels will result in noticeably higher prices, especially ultrawide 