yup, and if you looked youll see why i posted the second image. That shows the real Jekyll as to what he would/ might have looked like from an earlier perspective. and now here as well
that one is a re-creation from the movie "The League of extraordinary Gentlemen" which added many famous novel characters together (of which id definitely recommend for this month theme), Willhelmina "Mina" Harker from 'Dracula', Captain Nemo from 'Twenty Thousand Leagues Under The Sea', 'The Invisible Man', and so on.
That version was depicted as it suited audiences at the time period. i believe 'The Hulk' came out that same year so it was probably a convenience. Either way it worked and very well could have been brought up from fictional spin offs. Much like how Frankenstein's monster came synonymous with the mad doctors name, or how the monster itself in movies became a brute rather than a gentle giant that he became in the novel.
Its all about how it suits the current viewers and what would be appealing to them. Apparently a giant Hulk very much appeals to today's audiences, i mean i was sold i liked that movie even knowing it was bad! The one i posted is probably the closest you could get to the original novel, even though he still appears to transform into a monster.
Either that or... you could go with the 8-bit Mr. hyde, that one is "spot" on i say