Now I watched ANH again last night, and the shot used is not there. So it makes it difficult to put it in the film. I would almost need another shot from earlier in the scene with either Leia's head down or her looking away as not to see her mouth move. Because right after the planet is destroyed, we cut to Obi-Wan on the MF 'feeling' the planet being destroyed.
Just thought I would share.
Here is the clip.