I just asked because I saw this socket without cable for PS2, and also others, but not for Saturnfor Mega drive regular DB9
saturn and playstation sockets from aliexpress
So there is no problem in having the 3 option there, just not connected at same time. OKbad idea, for example, saturn controller fine work without VCC (he get power over internal pull up resistors)
By the way nice printed case.
Thanks and great job