The diversifiers are mostly for fun, so they’re left a little ambiguous to be open for interpretation.
That said, my intent for “by the hand” would not include mouse in software, or even using a tablet. It’s more meant for scanning hand drawn images, although I suppose you could get a similar effect through software.
For “who needs pixels” there’s no limit to sprite size but the game screen needs to be 16x16 pixels or smaller (though it can be, and probably needs to be, scaled up by some multiplier).