Sprite import format?

Could someone lay out the formats/requirements for importing textures for a 2D game that is from Photoshop? I have watched videos of people importing character movements and not all are always the same specs. Should the format be .png? Should the height and width be 512 x 512? And any other details that should be changed to before I import it into the UE.



Bit Depth:

File size:


The image below is from a tutorial I am following along. But this is an example of what I will be creating in Photoshop. Things like environment, characters, and any other assets.


Also for the images in the sample picture above should I create each frame as a separate image then use a sprite sheet software to create a sprite sheet?