oh; right. Well; yeah it’s a shader, just the default one with interpolation set to nearest pixel (or filter to none, or crisp, or whatever depending on the framework) for the asset.
Iirc I’ve also rendered to a smaller canvas and resized for rendering only)
this is basically what the Internet suggests for drawing rotated and/or scaled pixel art.
hope it helps
—- Edit - this is what I would do. But actually the thing above is just a drawing; and it was rotated in aseprite. Anyway - I recall Nuclear throne (and countless other games) do it similar to how I described, give it a try :)