How many litter boxes do you have? Maybe she'd like her own-I have 3 cats & 3 boxes. 2 both use the same 2 boxes but 1 will only use 1 specific pan. Try getting 1 more pan just for the one cat-a cheap enough remedy before trying vet visits to make sure nothing else is wrong! Good luck and congrats on the new home!
Before you moved, did all 4 of your cats use the same littler box? Maybe she just needs her space. What if you put her in maybe a bathroom with her necessities...bed, food, water, and her own litter box for 24 hrs. Maybe she would use it and get back in the habit of using one. Ideally, she could go outside. We let ours out during the day and they spend the night in the garage because there are predators in the area. They also spend time inside as well.
Once she goes out this will stop I guess shes telling you she wants to be out, when I move I find 2days is enough and then I go out with mine a lot to watch what happens .From what I read it takes cats a little while to adjust to new surroundings ..good luck