Achieve True Color in Unreal Engine: Disabling Tonemapper (+ Color Grading)
r.TonemapperGamma=0 r.TonemapperFilm=0 r.Tonemapper.Quality=0 r.ToneCurveAmount=0 r.Mobile.TonemapperFilm=0 r.MobileTonemapperUpscale=0 r.EyeAdaptationQuality=0 ...