As for Aquanox Deep Descent:
The only way I can lower the blur is by setting postprocessing to medium or low. I play in 4K on a large screen, and it looks more like 2560x1440 than 4k. Please give us a separate options to get rid of the postprocessing blur while keeping the postprocessing fidelity and the picture sharp. I'd play at 8k with downsampling to 4k, but my GFX card is not fast enough (Titan RTX).
That is just about all I have to complain about for now - rare for someone from southern Germany.

Attached Screenshot explanation: Green are areas which are as sharp as expected. Red blurry hell. Well the whole actual game is a blurry hell. You cannot leave it that way, I will refund if you leave it that way, I play on 4k not on 1280x720-upscaled.

Solution: Luckily it is an Unreal Engine game.

C:\Users\<username>\AppData\Local\ANX\Saved\Config\WindowsNoEditor\Engine.ini

Add:

[/script/engine.renderersettings]
r.DepthOfFieldQuality=0
r.DepthOfField.MaxSize=0
r.SceneColorFringeQuality=0
r.MotionBlurQuality=0

[SystemSettings]
r.DefaultFeature.AntiAliasing=2
r.TemporalAACurrentFrameWeight=0.1
r.TemporalAASamples=8
r.TemporalAASharpness=1
r.PostProcessAAQuality=6
r.Tonemapper.Sharpen=0.8
r.ScreenPercentage=120
r.FogDensity=0.2
r.ViewDistanceScale=4