I am in preproduction of a card-based game (think Hearthstone). What engine is the best for that type?

3D or 2D? And what the requirements of your game? Are you programmer? C++ one? Not enough info

I'd use Python with pygame, and some free set of card graphics.

There are several good CCG engines out there, what engines have you considered so far?

If you haven't considered any, a google search for "CCG engine" pulls up several.

I think 3D would be much better and appreciated now a days.

I am in preproduction of a card-based game (think Hearthstone). What engine is the best for that type?

For reference, Hearthstone was made in Unity.

Hearthstone did use unity like Lactose said but again that is not really your only choice. UE4 can easily do a card game as well. Unity and UE4 are the top engine players but really almost if not all engines out their can do a card game. With that said it would be good to keep in mind that UE4 has blueprints which can be very advantageous for prototyping or even making the whole game with. Ultimately the choice is yours as you only know the kind of experience you have to work with.