Hard to say. I don't think Froch would have crumbled so easily vs a Pacquiao level fighter but he would have been battered properly nonetheless. Froch had a better career imo but I'm not sure he was better when both were at their prime...
Im not so sure Hatton was better. While he probably has the better win (tszyu), Froch toughness might make him better. Hatton chin, while it wasn't glass, was a bit suspect. Tough one to call to be honest
For me it's Froch. As weird as it sounds, I just think that he has a more applicable style / attributes when facing a variety of top fighters. He is an underrated feinter, for example, and he is just generally hard to gauge for all but the best around his weight. Not slating Hatton, who I actually think is underrated by most and was a wicked body puncher. I guess it helped that Froch was a disciplinarian in regards to training whereas Hatton was too casual, to understate it at the least.
If Not for Andre Ward, Carl Froch Would Be the OBVIOUS Answer...But He Was Never THE MAN In a Division, Which Hatton was @ '40... Froch Has a Better Resume, But Hatton was More TALENTED Also...Superior Footwork, Hand/Foot Speed...Better BODY Puncher, As Good of a Puncher to the Head...Hatton was More DYNAMIC, More EXPLOSIVE... REED Actually LIKES & REWATCHES Froch More (Among the BEST Resume's of His Era, Unquestionably) , But Hatton's the Answer, Objectively Speaking...