This script sets your image to a blended EGA palette then dithers it to the original EGA palette.
It can be downloaded from https://invisiblespiders.com/egaify.zip
There is also an intro video available at Introduction to EGAify script for Aseprite - YouTube
Feedback is welcome.
Hello Dan, thank you very much for creating and sharing this script!
I have added it to the script list of this post, I hope you dont mind ^^
Aseprite 1.3 beta introduces a bug where if the same colour appears in the palette twice it selects the one closest to the end rather than closest to the beginning.
Because this script uses the palette position to work out the two mix colours this was throwing off any instances of black in the image.
This is solved by changed all non-used palette swatches to partially transparent.
Now it selects the black swatch at the the first index position again.