Change NoReloadOnInit=0 to 1 in your Reshade.ini file. Then open up the Reshade menu and reload all shaders ONLY when you're playing or inside a level.
Xash3D has this weird thing where everything loads up at once and runs at a borderless windowed mode of sorts. The important thing is trying to compile as few shaders as possible.
Here I'm using LUT, Technicolor2, FilmicAnamorphSharpen, VHSPro and Deband.
Edit: Scratch all of that, shooting once at a wall shows textures are still broken.