why did you make models so low-poly?
If you add at least +500 triangles, then the model will look much better and the animation is without wrinkles.
How many triangles in the models now?
In fact, little has changed if you do not make the model "for the future." Modern computers (even those which are already 3-4 years old) working in 50 times more polygons than any of the existing locations in the game.
PS: Im speak English very bad so excuse the mistakes.