Hah, someone just got arrested in Australia for trying to import a child sex doll.
Sex robots made to look like kids would probably fall under the same laws of depiction of underage sex.
However I think they might be legal in Japan, where the creepy-ass dolls came from, where they're seen as an acceptable way to get the pedo out of your system.
But still, I mean ewww, I can't imagine anything worse to have discovered in your closet.
But you know eventually somebody's going to build robot kids, and somebody else is going to try and fuck them, whether they were built with that intended or not.