The issue is certainly Unreal only.
The example is basically:
Parent
—Child (rotated 90 degrees on the horizontal axis, offset to sit at the origin)
Here is a comparison between Maya, Unity, and Unreal, when you scale the parent on the up axis
The issue is certainly Unreal only.
The example is basically:
Parent
—Child (rotated 90 degrees on the horizontal axis, offset to sit at the origin)