I’m not sure if you can tell this young with Appleyards. Eventually the females will quack and the males will make a rasping noise, and the males will also have curled feathers on their tail. But unless voice differences are discernible this early (not sure as I only have Muscovies), I don’t think you can tell.
These are WH's, yes? Did you get them as hatchlings? If you have any pics within the first 3 days of hatch we could make decent guesses. They can be sexed by bill color with 70-90% accuracy after hatch but that window is small. Boys have darker bills, girls are lighter with a dark tip.