Blinking 2d paper sprites

Hi everyone.
I am new in UE4, so for practice I decided to create witch saga like 2d game.
For now I got problem with blinking sprites.

Link to frapsed movie:

Description:

We got an object in 3d environment. Object got 4 components: root and 3 attached to him sprites. (Cannon top, arrow, Cannon bot)
Object got root in 0.0.0 transform position.
We rotate root, to rotate all sprites, attached to object. (Orienting cannon to mouse pointer).

Sprites got different local transform:
0.10.0 for CannonTop
0.5.0 for Arrow
0.0.0 for CannonBottom

Therefore we must always see CannonTop sprite first. Then, if he got opacity - we see arrow, then if Arrow got opacity - we see CannonBottom

World Location of thes sprites in game:

0.10.0

0.5.0

0.0.0

Seems legit.

But in game sprites blinking. Same effect you can see if you set sprites on the same position. (Sprites got same Y coordinate)