Jeremy Wilson’s review published on Letterboxd :
It probably says enough that the best aspects of Hansel and Gretel: Witch Hunters are the opening credits sequence and a pace that borders on breakneck. That's not to say that H&G:WH is terrible per se. It's just that nothing else about it rises to what I would call "good." Mostly, it's just uninspired, easily digestible filmmaking. It is a more enjoyable moviegoing experience than similar films such as Van Helsing and Abraham Lincoln: Vampire Hunter, which are both hideous. Its tone is lighter than both of those movies as well, relying on a plethora of anachronistic weapons and dialogue featuring numerous F-bombs. Its tongue is also pretty firmly in its cheek, which helps. Renner and Arterton are fine, although Renner in particular looks like he's going through the motions in numerous scenes. Famke Jenssen is pretty fun as the villain, but none of the other supporting players stand out (there is a troll that actually steals the few scenes he's in). I think many will be happy that it earns its R-rating. In addition to its F-bombs, the movie has plenty of bloody violence and some nudity thrown in for good measure. Like I said before, it also rarely stops or slows down, always hurtling forward toward its predictable and franchise-extending conclusion. It's not very scary or funny or dramatic...but its visceral pleasures are enough to get it to "average."
It's not great by any measure, but there are certainly worse ways to pass an hour and a half.
Oh also...Hansel has diabetes. From all the candy. Seriously.