This is something that might be too close to call. Some will undoubtedly go with Brody because they simply like him more and vice versa for Stan Hansen. We honestly don't know how much money each guy drew and most of what we have to go by is based on how visible they were.
Stan Hansen spent most of his career in All Japan Pro Wrestling with an occassional run in the United States. Hansen is and remains a wrestling god in Japan and has had more success in AJPW than any other foreign wrestler before or since. Probably his most memorable accomplishments among American fans includes a 180 day run as AWA World Heavyweight Champion and a 50 day run as NWA United States Heavyweight Champion. Of course he did win more straps in America, but those are easily the two most prestigious.
Bruiser Brody was pretty much always a free agent. He never stayed tied to any particular company for too long and was always on the move. Brody was a huge star no matter where he went whether it be Japan, United States, Puerto Rico, etc. and was a big draw wherever he went. Brody was also a huge star in AJPW like Hansen but Brody's biggest success in general was probably in World Class Championship Wrestling. I've read accounts that, in 1985, Brody was earning $14,000 a week as a result of a bidding war between All Japan and New Japan. Even today, 25 years later, making $14,000 a week in any profession is damn good money. But this is in 1985 dollars so that was just a huge sum at the time. If the $14,000 per week story is true, then Brody must've been a huge draw in Japan in order to command that type of salary.
Based on that, I think I'd have to give the edge to Brody. There's no real way of knowing which of these two legendary brawlers was the bigger draw, but the story about Brody's huge pay in Japan in the mid 80s does give some indication of just how big of a draw Brody was.