For the US tg-16 according the the back of the console itself, it uses a 10.5V center negative dc adapter. A genesis 1 adapter (important a model 2 will NOT work) or equivalent will work just fine. In my experience model 1 genny adapter can range from 9 volts to 10.5 volts. Also a genny model one adapter can be used to power a jaguar and possibly a nes, and if you have a third party one with a two tips, a snes and sega cd as well.
As far as a region mod goes, nat would normally be your guy, but he seems to be missing as of late. He is probably just busy atm. If he can't take you I probably could, as I am no stranger to console mods. Although it would have to be after sometime in mid august, and no guarantees I will take you. There is also another member who recently took up doing mods, but i haven't heard from his endeavors in a while either, turbo something i believe it was.