Hey,

I'm curious about art styles, and I'm wondering if people can make cartoon-like characters and environments using a 3D software, like Blender? IIRC, Cuphead was drawn by hand, and much of its success was due to how it looks.

Is it possible to replicate such “graphics” in Blender, if the goal is a 2D platformer game?

Yes, it can be done. Blender is a capable 3D modeling and animating program. It takes skill and effort from the artists, animators, and other developers, but the tools are capable.

As for a 2D platformer, that opens all kinds of definitions. One style which works well with 3D objects is to have a 3D world where player interactions are constrained on one axis. This is how engines like Unity implement their 2D settings. You can have a camera that exists in 3D space while the players are operating on only two of those dimensions. You can also have worlds that are entirely flat like the old NES-era side scrollers, that's less good of a fit for 3D models. You can have games that render out 3D viewpoints to create images used in the 2D game, which can work well for 1:2:1 and isometric games, or other viewpoints where you want to create the images from a more complex model. That option is far more work, so unlikely from a hobbyist unless that's a critical focus for the game.

Blender is not going to be the limiting factor. The people working on your project, their abilities, their time, their schedule, those are going to be what limits you.

Blender can be used for animating 2D characters too: 2D Character Animation by 3dmotive - Blender

Blender is most certainly capable of making pre-rendered sprites, yes including for platformers. I'm not sure how easily you could duplicate that hand-drawn style of cuphead(not sure you would want to either), but there are plenty of unique styles you can pull off. There are advantages to this method over 2d methods too.

1. You end up with 3d models. This means you can bake out normal maps(if you want to use a normal mapping shader in your 2d engine of choice). This also applies to AO, specular, etc…
2. You also get advantages in the iteration stage. You can tweak an animation and re-render. You can change a material color and re-render. These iterations generally take much less time than if you had to re-draw all the frames by hand.
3. Like in #1, you have 3d models. As long as you didn't skimp too much in the details, you can use those models for other things, like backgrounds, title screens, and even things like promotional materials.