Need advice - 2d Sprites sequence (no sprite sheet) & normal maps

Hi all, we have a problem about normal maps. We use a lot of sprites sequences for our bosses and big sprite objects.

same as this because it's too big (X/Y) to be a sprite sheet

We need to know if : there is a way to use this animation (frame sequence) as normal maps ? how to apply ?

or do we need to create a second animation with the normal map frame ? how to apply ? or do we need to add 1 shader at each frame on the original animation ?

Many thanks to help us on this one because we are a little lost. Sorry for my bad english.