Alter window distance
Window light is soft because daylight pours through a fairly large opening, and the size of the light source determines how soft the light is. But we can control the light to a degree by moving the subject. If she’s close to the window, the light source is larger in relation to the subject so it’s softer and fills out the shadows. But move her further away and the light source becomes smaller in relation to the subject, so the light gets harder and more direct.