Hey there! I played with Aseprite’s data files for a little bit and it turns out that you can actually import your own custom ratios by editing a text file. Take a look!
New sprite window
Sprite properties. Those pixels certainly don’t look a 1:1 pixel to me!
You have to edit 2 files to show the custom ratio in sprite properties and the new sprite window.
Keep in mind that this might cause some bugs since I don’t if we should even do this. Only @dacap will be able to let us know whether it’s fine for us to mess around with the internal settings. But looking at the structure of the config files, it looks like it’s designed to do this kind of thing.
I made a guide on how to add custom ratios HERE.