Couple things that might help (or did with my DD)......
1. Find some video/pictures of pitchers who are doing what you're wanting her to achieve. What she's feeling vs what she thinks she is doing are likely two different things. Let her visualize what she needs to get to.
2. Work with her getting her stride leg knee up more (think 90-degree angle) with toes straight and up. *The foot/toes being straight and up (as possible) isn't an end all/be all for everyone. This is just something that helped my DD.
3. Really work on the plant/brake leg. The brake is so important and is meant to hold everything back so the energy transfers to the ball. It could be (based on her age) that her core is weak. Often, this is something that kids ages 12-16 don't work on. And for kids who have had recent growth spurts, the core can be especially weak due to being stretched out. If she were to work on her core a couple times a week, she'd see a few things with her pitching improve.
1. Find some video/pictures of pitchers who are doing what you're wanting her to achieve. What she's feeling vs what she thinks she is doing are likely two different things. Let her visualize what she needs to get to.
2. Work with her getting her stride leg knee up more (think 90-degree angle) with toes straight and up. *The foot/toes being straight and up (as possible) isn't an end all/be all for everyone. This is just something that helped my DD.
3. Really work on the plant/brake leg. The brake is so important and is meant to hold everything back so the energy transfers to the ball. It could be (based on her age) that her core is weak. Often, this is something that kids ages 12-16 don't work on. And for kids who have had recent growth spurts, the core can be especially weak due to being stretched out. If she were to work on her core a couple times a week, she'd see a few things with her pitching improve.