5.1 The UMGs below will still be obscured when the animation is played

List:
Overlap:
Size Box:Image
UI_Other

UI_Other:
Image

the Image of UI_Other will SetOpacity(0) in NativePreConstruct()

But When the Image of UI_Other PlayAnimation,the Image will be masked by the Image of the Size Box,I can’t understand

You mean the Opacity doesnt take effect ?

Try to play around the ZOrder if that can help.