SMAA+Lumasharpen+16bit color = dark screen

Accidentally I set the color depth to 16 bit in Dawn of War Soulstorm and then the screen is too dark if SMAA is combined with lumasharpen. (Reshade 0.16, SFX 2.0 Preview 8 ) but it's probably unimportant.

16bit formats usually do not support SRGB, but SMAA needs SRGB or otherwise gamma correction doesn't work, which results in the dark screen you experience.

I don't think so because SMAA alone works fine with 16bit color depth and older SweetFX versions had similar bugs with lumasharpen. Afair I had bugs with dark screens with lumasharpen without the use of SMAA. And this all under 32bit color depth.