I'd have to check, but I'm fairly sure the freely available libraries do already exist. It would depend on what kind of game you were making, but the same kinds you'd do on NES or SNES could likely be handled fine.
By support that could mean information on swap tricks, boot discs, programming PIC chips to act as modchips, using game enhancers to boot the game, etc. You're right that depending on the country there may be different laws that may apply.
But I think that the market for these games is generally going to include people that are willing and capable of more than just putting the game in the system.