Cool, I will try that one out. I'm often using ESRgan that supports transparency. I don't think waifu2x does that. Without that support, some textures could be bugged.
There are good 1x and 2x models for ESRgan here upscale. If you search “ESRgan models” there should be “Artifact Removal”, or other anime based ones.
You could try that.
Or just go with ReShade for Vulkan.
For example there is one fun shader called “AdvancedCRT” if used correctly it can create cool effect of pc-98 anime dithering on textures, not only adding nostalgia, but also some shadows. There are a lot of things you can do in it.
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Link:
Models for ESRgan: upscale. wiki/wiki/Model_Database
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Apparently there is ReShade’s modified version called GShade. Straight out of Phantasy Star Online 2 community. Adds more functionality, a lot of presets, presets converter, outside of game Control Panel, better performance and growing support for online play.