I started doing this for the sole purpose of making expressions look good. I did this by doubling the size of the original sprites and using normal size pixels to edit them. I know this wouldn’t work on retro consoles that use pixel art but I don’t think it would look as good if I went by the rules of pixel art.
If you want to do this in your pixel art (which I don’t recommend because only freaks do that), I think it’s only necessary for expressions and not poses. I think I just triggered all the pixel art enthusiasts >:)