Just taking a break from other things. I didn't spend more than five minutes on this, so it isn't perfect. But one very good method to blend a shadow is to create duplicate layers, try Gaussian blurs and/or motion blurs, create layer masks on the blurred layers, then paint in the blur over the original shadows. Here I used a gaussian blur layer mask and a horizontal motion blur layer mask to smooth out most of the shadow on the cheek. More could be done to make it seem more natural but you get the idea. There is still a faint edge of the shadow but another round of layer masks would smooth it out. Going back with another layer mask of the duplicate image with a tiny amount of the Add Noise plugin could make it all seem quite natural.