Reducing Sprite Atlas subtextures count

Hello!
I know that there is a way to make sprite atlas smaller by creating a downscaled variant.
But if sprite atlas has many sub textures, say 2, how can i create variant not by resizing this 2 sub textures but by resizing sprites inside and creating 1 sub texture with same size (for preventing possible loading spikes in the middle of animation and decreasing draw calls)?

It will be great if we could make sprite atlas variants by resizing quads inside texture, not by resizing textures, that will reduce subtextures count

 

Also, if there is a way to "bake" spriteatlases so i can delete all N * 500 sprites to prevent long editor loadings every day?)

 

Figured it out, to reduce sprite atlas texture pages i can just generate bigger atlas then set max texture size in platform specific options if needed)

 

To "bake" sprites i just can use external texture packer