Sims 4 PS4 Won’t allow me to create character

There's something you could try until they fix this issue, though if you're making big families, it'll take some time. What you can do is make each Sim individually, save them to your Library, then when they're all done, go back into Create A Sim and Merge them all into one household. You'll still be able to edit their relationships this way, so you can still set them as being family. Then save the big household to your Library so you don't lose them.