Would probably be better if you had the two different art styles taken from the same part of the game. The first one seems to ooze more character, the second seems more indie/ arts and crafts. I prefer the first, but my initial reaction was that they were the same art style, but taken from different parts of the levels. If internally you aren't 100% on this art style and your alternate is similar, perhaps you need to create something even more different and see what you think about that. Good luck.
I like the top one, as it fits more with your description of the game in general ("[It] is supposed to be a comedic action platformer but a violent one"). The bright colors in the first picture properly emphasize the tone you seem to be going for, whereas the bottom picture seems to depict a darker setting with a more serious tone.
Than again, as some of the previous commentors have pointed out, both screenshots be in the same game: they use similar tiles for the platforms, and the art style is practically the same. I wonder if what you're truly trying to ask is which screenshot properly depicts the tone the game is trying to present. If this is the question you're trying to ask, then I would answer with my previous answer.
Regardless, I hope my and everyone else's feedback help you in developing your game for the better.
The first one gives me a better impression in general. It's full of interesting stuff. The second looks like an empty corner of a level you're supposed to ignore.
Edit: now reading through the comments I do like the grass in the second one and how dark and somber it is. Just now noticed the bodies hanging in the background. I find I like them both! The 2nd feels like a night cycle to the first, almost.
I like the 2nd one. It seems to have more details in the design i.e. the skeletons, people hanging from the cliff, etc. I like how you made the background of the 2nd screen layered with different shades/silhouettes, which, in my opinion, leaves more room to be more creative with the backdrop without the risk of confusing the player between the actual level and the background. Also, I like how in the 2nd screen, the top platform actually gives a shadow effect on the area beneath it. Appreciate small details like this.