It's very strange because if it was a change tied specifically to the animations then the behavior would be the same for the player and NPCs. However if you take for example Scarlet Aeonia, when used by Malenia she clearly has Hyper Armor, but when used by the Player hyper armor is not present. The animation, however, is exactly the same, only the parameters (as attacks damage, spell effects etc.) are different. I'm really at a loss on where the difference lies, and it's not just a matter of poise difference either since other skills used by the same exact NPC don't have hyper armor (the same as it happens for the Player). I've spent the last five days trying to find out a solution but alas, I've even more clueless now on how hyper armor works than I was when I started.