@AxolotlAvery Okay. Are these accessories new or ones that you've had for a while? Have you been playing since the early November update? You may want to check with the creators and/or the sites where you got them to make sure you have the most updated versions. I wonder if those accessories might be broken and no longer compatible with the game. If they are up to date, then it may help to remove them and do a game repair. After doing the game repair, try deleting the localthumbcache.package file located in the Documents / Electronic Arts / The Sims 4 folder. Then put one of the CC items back in the game and test it. You could also try testing each CC item to see if any of them show up. If you have a lot of CC, maybe divide them in half and alternate testing each half and continue dividing them to see if any will work.
Edit: I was just thinking maybe you could give the description of an item that isn't showing up so I can get it and test it as well. Please don't post a link, just the name / description of one or a few of the CC you have so I can search for it.