@Digi [FiM]  
Not really. Luna’s spine connects at different locations, her head is joined with the neck at an odd angle and far more forwards, shoulders are angled farther back, her hips and leg joints are at more acute angles, and her musculature varies widely from average to thin compared to Tempest’s more evenly distributed, stocky build.
 
Of course, it’s something that doesn’t become extremely obvious until you try and draw both of them and break down their skeleton, musculature, and their postures and realize how more naturally and solidly built they made Tempest compared to pretty much every other pony in the movie. (which makes sense, since she’s supposed to be so athletic)

i dont get it, the only real difference between tempest and luna is that tempest has a girthier neck and is a tad taller. otherwise they have the exact same body build

@BK Leonidas  
I wasn’t aware you were joking, sorry.

@Dogman15  
I know. I was joking.

@BK Leonidas  
She didn’t. That’s an animation error or an edit.

Geez, she finally gets some meat on her and you’re already on her newly formed ass.

I noticed something else. When did Celestia change eye colour?