Overall I think her technique looks great! Here's my analysis.
My first impression was that her overall stroke reminded me a lot of Rafael Nadal.
This is a great model. As you can see, her preparation looks great, she has two hands on the racket and is ready to prepare for her unit turn.
Still looking pretty good.
However, as previous posters as mentioned it would do her good to keep her hand on the racket slightly longer.
As you can see, Nadal's shoulder has turned so it is at least perpendicular to the net.
Your daughter's shoulders are probably about 75% of the way there.
This should be a pretty easy fix and should help her develop easier power.
Here's where things start to differ.
When Rafa starts hit forward swing he pronates his forearm.
This is evident by how the back of his hand is pointing skyward, as the arrow indicates.
This causes his racket face to point directly at the ground.
As you can see, your daughter does not fully pronate her forearm and therefore the back of her hand is pointing backwards towards the side fence.
This causes changes in her racket position at contact, as we'll see later.
As you can see here, your daughter does a great job extending upwards into contact.
Looks almost identical to Rafa minus the changes we noted in the last picture.