Problems with equipments [2D]

Ok, so... I want to make a PNG animation 2D player, and not a skeleton one. But, how could i put equipments in him? Like, i have to animate every single piece of armor at it's own, and let's hope that it will match with what the player is doing? It seems craziness for me, will make possibility of so many bugs... I have no idea, for a example of what i want to do, look for the game The Binding of Isaac: Rebirth, there's hundreds of items, and the player seems to be previously animated in PNG.
I hoping someone knew the answer. Sorry for my english, i'm not from english countries.

 

The solution to the problem you pose is bones/skeleton - OR a lot of hours animating individual pieces/sprites.
There are several software solutions available to create sprites animated with bones, and several in the asset store that are tightly integrated with Unity.