syncing hit detection with animation in UE4

Hello everyone,

I am trying to figure out how diablo4 does the new animated hit detection in this video:

As you can see the gree damage area gives a better feeling of “hit”. I really want to simulate this in unreal engine with c++. I have created a simple scenario: player clicks on attack, animation montage plays attack animation, in the exact hit moment a custom animation notify gets triggered. Custom anim notify logic does a SweepMultiByChannel with a shpere collision shape. My problem is that I can not create the exact shape as in the image below. How would I go about doing this in unreal engine using c++ ?