Fritzing doesn’t support non circular holes in parts. The only thing you can do is use an outline svg in the sketch to produce slots and that is a PITA and can’t be moved. Your best bet is to use a hole big enough to cover the slot.
Thanks Peter. That sure is a PITy! Lol.
Here’s a “round hole” workaround part for the same (PJ398SM) Jack socket:
PJ398SM-rh.fzpz (5.2 KB)