Maxis's EACade has announced that Maxis has identified a fix for mod loading:
We’ve identified the cause of the issue impacting CC and Mods, and are now working on the fix and timing for its release.
NOTE: This doesn't guarantee that they have found all possible causes. It also doesn't mean all your mods and CC will definitely work after that fix is released as there could be other changes that need updates on modders' side for some mods.
Also: I've in multiple meetings tomorrow, so if there's more info, it may come here a little later than you might see it elsewhere, depending on the timing.
