Watched Carrie Eberle (VT) pitch against Megan Goode (JMU) a few years ago. Both teams had girls behind the backstop using the radar on every pitch. Eberle was consistently 68-69 and hit 70 once. Goode was consistently 70-71 and occasionally hit 72.
It looks like a lot of these pitchers get close to ‘coiling’ with their lower body. Drive foot toes and knee point to 3B for righties, 1B for lefties before the back leg/hips drive through. Not much heel over toe.