In other news, I’ve been pondering making a PCE to TG16 adapter. The only difference between the two is the order of 8 pins are reversed on the edge connector. TG16 carts also have some rudimentary region protection that’s defeated by grounding a pin on a PC Engine.
Might it be possible to layout the pcb with a jumper or switch to reverse those pins for compatibility with both systems? Basically to have parallel traces and then define which path is used?