Will she let you handle her legs otherwise--can you brush them, run your hand down them, rub her pasterns with your fingers, things like that?
I've got a gelding that is very twitchy about the clippers. Last year I scissor clipped his legs (I didn't body clip him--he was shown full coated so I didn't have to shave his legs, I just clipped the long hair off the backs of his legs/fetlocks/pasterns. It was a struggle to even do that with his front legs but the hind legs weren't too bad--further from the ears I think, & he couldn't hear the snips so well. It's the sound more than anything that bothers him.
For the second show last year I used the clippers on his hind legs--but I turned a radio on loud right beside him & it hid the sound of the clippers. Front legs still had to be scissor clipped.
This year I clipped his hind legs with clippers, no problem, no radio required--front legs still had to be scissor clipped but it was a lot easier to do that than it was last year. I'm hoping that next year I can use clippers on him!
Have you tried stuffing her ears with cotton? I've meant to try this on my guy but never remember to buy the cotton until I actually need it. I'm thinking that if I could plug his ears he wouldn't mind the clipper sound so much. (Please note--running the clippers around this fellow does no good. I can clip his head and bridle path no problem--the sound of the clippers bothers him only when the clippers are down in the vicinity of his legs. Goofy.