Unreal Engine DrawDebugBox ScreenSpace.
Turns out I was just overcomplicating things, scaling up the extents based on distance simply works. Rotate the box so it faces the camera, and tadaaa
In Unreal Engine, what's the easiest way to debug draw some simple lines in screen space? Want to make a debug mode that highlights specific actors and draws some screenspace boxes (and text) around them so I can easily locate them in-game when playing