The behaviour I demonstrated in the animation is the default behaviour with just the Receive Hardware Input enabled. You need nothing else to interact with a 3d widget’s button + mouse click. Perhaps you’ve modified the behaviour of the button itself?
I do not know what else you’ve got going on in your project, what other interactions you’ve scripted. Consider testing it in a clean project:
- create a widget with a button
- embed it in a widget component and enable Receive Hardware Input
- drag the actor with the widget into the world
That’s pretty much all it takes.