How to make layered character + vfx + hover animation?


I have a following issue.
I want to make something like layering to make and control character animations:

-Character itself (idle, run, attack).

-VFX (e.g. VFX on attack). I prefer to have it on separate layer for ease of management.

-Hover/highlight. When you mouse over a character a designed frame appears around him.
So all these animations are supposed to be layered on top of each other.

There is also a constraint.
Animations are frame by frame.
All sprites are 500x500px PNGs with transparent background with character/vfx/highlight placed in specific place of image. This is necessary to have same format for different character sizes.

I wanted to make it with animation layers but it doesn’t seem to work for me.

I tried doing this with “Additive” blending and playing with weight.
Only one of layers seems to be active. Either only character or hover. E.g. if hover layer weight is 1 - only it is seen. If any other number - non of both is visible. If 0 - only character layer is seen.

Screenshot by Lightshot (character layer)

Screenshot by Lightshot (hover layer)

Is it possible at all?
Or layers are meant to be used only with 3D animations and masking?

Thank you in advance.

The only solution I came up with is placing all animations on different child objects.
And I’m not sure it’s a correct way to do it.