Y'all are going to hate me but I'm going with Irons being the poor man due to Dungeons and Dragons movie. Im letting that be the tie breaker.
Jeremy Irons is no stranger to putting his foot in his mouth either, but he's also the only actor in the entire cast of Dungeons & Dragons (2000) who understood the assignment and devoured every piece of scenery in a five-km radius and that kind of conviction deserves to be rewarded, quite frankly.
And as terrible as the movie and his performance is in it, he's the best thing about the Dungeons and Dragons movie.
Boy, lots of opinions on his role in Dungeons & Dragons (2000)
. I honestly treat it as a non-event in judging his acting. I mean, he wasn't trying to act 'well,' he was trying to salvage a bad situation. He found himself in a movie he knew darn well was going to be a nightmare and decided to still have some fun making it. Honestly, that's better than just phoning it in*, getting sloshed every day*, or actively trying to sabotage the movie**
. It's not quite to the level of Raul Julia elevating his part in Street Fighter (1994)
to a great performance in a bad movie, but what he turned out was entertaining to him and entertaining (if not good) for the audience. Mostly it's just a 'no score drawn' in my judgement of him as an actor.
*Bill Murray tried helping re-write the Garfield (2004) movie he signed onto after realizing the Joel Cohen who wrote it wasn't one of the Cohen brothers, but by the time they got to the voice acting, he had clearly checked out.
**John Leguizamo and Bob Hoskins with Mario Brothers (1993) -- who, btw, rarely catch the blame for that movie.
***More example than there ought to be, but a few that stand out are Whoopie Goldberg with The Telephone (1988) or Bill Cosby with Leonard Part 6 (1987), also arguably everything from Marlon Brando after a certain date.
Anyways, to the main question, I disagree with the binary of the poll and the premise. Jeremy Irons and Ralph Fiennes are not alike enough that I think one is the poor man's the other. Irons could just as easily be paired with Frank Langella (hey, they'd both have a scenery chewing role in a bad movie) in a 'X is a poor man's Y' framing and Ralph Fiennes with pretty much any other 55-65 y.o british actor (Christopher Eccleston, Cary Elwes, Hugh Grant) and it make as much sense.