I don’t think face position is even a thing. Faces are defined by their vertices, so you can only get the position of the vertices that conform it and the normal of said face. To get the “face position” you would need to calculate the “center” of the face which can be troublesome depending on the geometry, also, remember that faces are deformed when being animated so you would need to be constantly calculating a value that is ultimately unnecessary. Vertex is love, vertex is life.
If you are doing a raycast then you can get the point of impact, which I think should be enough for you to positionate your objects.