Animation Lag performance with TexturePacker

[timber knoll]

My graphist added a ton of new 2D animation for our Boss and now the animation cause lag spike.
I use texture packer for the spritesheet and the game use a 2D othographic camera.

My graphist is obsessed with asset size and want to only use two spritesheets. Each one make 100MB (the boss is big and has 60fps animation).

Can you confirm it is a bad idea ?
Do I have solution to optimize big spritesheets from texture packer ?
Something I am not aware ?

I use the default animation sytem (mecanim) with AnimationController and Animator. Do Animancer have better performance for 2D ?

[wheat rose]

Every performance question should start by looking at the profiler.