Generally, she looks pretty good. But, there is always something to fix...
She isn't getting her arm straight. Her arm is straight at 3:00, but she immediately bends it. She never straightens it again. She is supposed to be "reaching for the sky" with a straight arm, and then at 12, she breaks the arm by pulling down with the upper right arm.
So, she needs to do "half frames" where she gets open, takes the ball to 12, extends the arm as much as possible, and then throws.
Her right foot always crosses "the power line". It is a nasty little habit to break. You may want to have her practice staying to our right, her left of the power line by telling her to overemphasize her foot position.
Next, she needs to take the ball back "on the power line". She is taking it back at an angle, which causes the ball get outside of the power line plane.
This is a nit...but, she is going to have to hide the ball better. This is her taking the ball back. The hitters have a beautiful view of her grip. This doesn't matter at 12U or 14U. But, at 16U, the hitters will look for her grip to find out if she is throwing a changeup or any breaking stuff. So, might as well as fix it now. She needs to cover the ball with her mitt as long as possible.