Hello,
I see there are snac adapters for both turbografx and pc engine. I'm assuming, that since they are the same core/plaatform, this is merely to facilitate the different port style between the two regions. I just want to double check that if I buy one, the controller will work across all games in the core and not be region locked or whatever. It would be a drag if you couldn't play PC engine games using a turbografx 16 snac adapter.
As far as I remember; electrically the controllers function identically but NEC elected to use different ports for the PC-Engine and Turbografx. You would have to buy the correct SNAC adapter for your controllers. You can also buy port adapters, if you wanted to use a PC-Engine controller on a Turbografx or vice versa.
We have the Ultimate SNAC PCE, accurate gameplay, support for original PCE and TurboGrafx-16 controllers (Turbo support) or Controller Avenue Pad 6.
If you want to support for all kind of PCE Gamepads and turbo support, you don't need anything else 
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