If it helps, don't save your progress just quit and keep adding more cc until the sims' outfits are all fine again. If this works, you can try loading a backup save in the new Sims 4 folder, again with the minimum cc necessary to test. The point isn't to fix every outfit for every sim, just to see if any of the broken outfits look normal again, so don't worry about getting every single cc item. Copy over the cc the Library sims are wearing as well, but only those items, or a subset of those items. Move the entire existing folder out of Documents\Electronic Arts and onto your desktop, launch the game once to spawn a clean folder, and copy over the Tray folder from your old Sims 4 folder. Just as an experiment, take a look at your Library sims in a new Sims 4 folder.
