Right click the Warhammer Game Symbol in steam. Search for game files, Warhammer.exe -> RMB -> Properties -> Change high DPI settings -> Override high DPI scaling behavior. Scaling performed by: Application
Disable Fullscreen optimization

Set the camera to 85 on utltrawide resolution, because the picture is cut off on the top and buttom, and you need to see whats ahead.

Window Mode: Fullscreen (Borderless Window stutters)
Char Detail: Max
Shadow Detail: 2-3
Physik Detail: 2-3

Textures: High
TAA: On
High effects: On
Disable Screenshake: On
Weather: On
Warp Heat: On
Max Dead Bodys: 30
Everything Else: Off

Set your Max Framerate in your Driver, and dont use the ingame 60fps Option, because i only got 53fps when enabled.

If you want to use DSR you have to set your desktop resolution to the corresponding one.