They are different, it's just the difference compared to Med 2 is quite subtle.

Napoleon had different versions of the same derp face plus some uniform differences in the French 1798 units.

Shogun 2 had equipment differences though mods bring more unit equipment diversity.

I got to be honest that facial animations instead of unique weapons animations is quite sad... Never really noticed the mo-cap novelty before, adding small facial animations that "show the faces of war" is quite absurd.

Why waste time to stare at faces growling when you can curb stomp the ai again eh?

hehehe