Human face is 0.117 meters long
Human's face average height is 0.19 m
A: 0.19 m / 2 = 0.095 m as radius
B: 0.117 m / 2 = 0.0585 m as radius
Area of an oval (I'm assuming it is): 0.00436485 m^2
https://www.math-salamanders.com/area-of-an-oval-calculator.html
Human skin tensile strength: 21.6 MPa
Force: 94,280.76 newtons of force = 9,613.9619544 kg of force, Class 10
I'm assuming you have to use the face's height or length (I will be using 0.19 m, but idk if its either 0.117 m or 0.19 m, im not that knowledgeable)
Energy: 94280.76 N * 0.19 = 17,913.3444 Joules, Wall level