Since the default fog walls looked a bit too much like smoke I decided to make a lighter one.
Took a lot more to find the actual TGA files than to change them.

The 4 versions are:
Clasic White (DaS1), lighter version than than vanilla, similar to DaS1.
Frigid Blue, inspired by the Project Beast leaked footage.
Hellish Red, a bit how the fog walls looked in Lost Izzalith and Demon Ruins in DaS1.
Abyss Black, darker then vanilla, looks like black smoke.

Installation:
1. Copy your desired fog wall files to "textures/DarkSoulsII/override" inside your GeDoSaTo directory
2. Make sure that you have set "enableTextureOverride" to "true" in GeDoSaTo.ini
3. Happy summoning!

Uninstall:
1. Remove "9f159d1b.png" and "333ec839.png" from "textures/DarkSoulsII/override" inside your GeDoSaTo directory.

Special thanks to Durante for GeDoSaTo.