Any way to save sims inventory when moving to a new save?

Might work to build a room or house, add the items in there, and save to library/gallery. Don't expect all names to be transmitted though, but at least you should get most of the deco for the visuals.

I don't do this often myself, so I have absolutely no idea whether it still works.

PS: did you try fixing your save by removing mods folder, deleting caches and repair game?