stacking, preventing the accumulated frames from becoming a pure white blowout. How to "Develop" the Look
MagicBloom.fx
While not exclusively for long exposure, these contain "exposure" sliders that help balance the brightness after you combine multiple frames. (Remember: combining 4 frames makes the image 4x brighter if not tonemapped).
ReShade long exposure turns standard gameplay into digital art. By mastering frame accumulation and motion shaders, you can capture the kind of ethereal, professional-grade shots that were once reserved for high-end DSLR cameras.