Maybe you can temp her playful side. Put the hose near her mouth and see if she plays with the water. Mine is like a dog that way. He'll put his lips up and bite at the water if I hold the hose there. Once he saw it as a toy, I could spray him anywhere.
I spray my horse in the face too. Meaning, I've sprayed the hose upwards and let it fall down on them like rain. Or I keep it at a lower pressure and use my thumb to spray her cheeks and forehead. I also find it helpful to run the hose up their neck towards their face and let the water run down their face from between the ears.
"Great spirits have always encountered violent opposition from mediocre minds."