Sugar Apple is hard to find without frizzy hair. It's like finding a white Cherries Jubilee. Darned near impossible, so her curls looking frizzy as they are? Very normal, and I don't know what trying to take them out of factory set will really do for her. . .
My last swap, my partner DID find me one with SOFT SILKY curls, but it is RARE as heck! Leave her alone, just a spritz of water to clean out the dust, but make sure it's cool. Hot or even warm water can pull the curl out. The scented hair ponies DO have frail hair and that's why gets frizzy just from shelf life.