To compare the difficulties of the two games, I will use my experience from the first time I played the games, and I will be using the original games of Ocarina of Time, not the Master Quest.
I played Ocarina of Time after I finished Twilight Princess, and I found OoT harder than TP. Mainly, I look at difficulty from the perspective of dungeons and bosses. And in both of these cases, I found Ocarina of Time to be harder than Twilight Princess. I actually got stuck a few times in the Forest Temple, Water Temple, and Spirit Temple in Ocarina of Time, but other than the Lakebed Temple, and maybe in the City in the Sky, I never got stuck all that much in Twilight Princess' dungeons.
In TP, I did not see the bosses progressively get better that much as in Ocarina of Time. Argarok, where he should have been very hard, wasn't very much harder, than say, Morpheel. But Bongo-Bongo and Twinrova, for me, were somewhat more difficult that say, Barinade and Phantom Ganon.
Work to be done in between the dungeons was also harder in Ocarina of Time, in my opinion. I didn't know right away that after finishing the Water Temple that I should go to Kakariko Village. But I never quite had a moment like that in Twilight Princess.