Epsxe had a special sub filter application that allowed shader packages to be used for certain mods/filters. It was janky as hell, but when it worked. It worked very well. They're difficult to find nowadays because the old hosting sites are nearly all gone and nobody gives a shit given that Duckstation can do it just as good with warping correction, too. And, has proper 2d/3d upscaling combined. However, here's a few examples of how good some of the old Epsxe filters looked
This article is from 07 (Jesus Christ)
https://racketboy.com/retro/enhance-ps1-graphics-with-the-best-epsxe-plugin-settings
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Here was the "best" general settings for Epsxe. Dat "Widescreen" "fix." The shader effects for natural vision looked really good. Not as good as Duckstation does with high resolution and geometry correction, doh
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Anyway, this is ancient history. OP should use Duckstation. It's better than the results I just gave by a country mile and should work even on a potato.