The PS4 capability isn’t even in private beta yet
Fallout 4 had mods for PC right off the bat, and Xbox One just recently hosted themlast month, but the PS4 precedings aren’t going as swimmingly.
Mod support isn’t even in private beta on the platform yet, and evidently a new update for the game messed with some things internally. Right now Sony is limiting mods to 900MB, whereas the limit is 2GB on Xbox One. Memory and performance issues while using mods on PS4 is also a problem — oh, and there’s audio bugs abound, too. Bethesda is working directly with Sony on a fix.
For now, it sounds like PS4 mods might get pushed back a bit. They already had a hell of a time getting Far Harborup to snuff.
Creation Kit 1.5.4 Update: PS4 Mod Upload Support[Bethesda]