who cares what might potentially happen very occasionally in multiplayer?
whenever anyone suggests allowing players more actual ability to play someone comes along and says that would be a bad thing as people would exploit it in multiplayer
If you choose to play multiplayer with the tiny minority of infantile idoits who would name their children after swearwords then you have to suffer the consequence of putting up with it. You should deny responsible players features because you fear a tiny minority offending you, when its your choice whether or not you involve yourself with them.
thats like saying pens should be illegal because some people might write swear words. Its not a sensible argument and it never will be.
Most people would use that function responsible and it would greatly increase gameplay, it doesnt matter if it might give unpleasent results in multiplayer.
As it is, every time a child gets born you have to save, edit the save and then re-load the game just to have any authority over sons names, giving a choice between randomly generated names wouldnt solve that. Letting players enter their own as EU3 allows for province renames is the simplest and in my mind, best way to do it.
Dont punish the majority because you fear a minority.