As I mentioned on the RetroArch’s Discord and in the Please show off what crt shaders can do! topic I made a script for Windows 10 and Linux to use a save state to obtain every possible screenshot with each shader selected in RetroArch for any of the video drivers.
Here’s a link to the GitHub: https://github.com/Seriousattempts/ShaderScriptContainer Windows 10 YouTube example: https://www.youtube.com/watch?v=fM8buydFWu0 Ubuntu YouTube example: https://www.youtube.com/watch?v=dbQoGDej9G4
Note: On Linux, it will delete every screenshot within your screenshot folder and it zips up the file.