I’ve written about crossing the impossible path of Gen I/II to Gen III a few times:
- Lanette’s Poke Transporter lets you transfer Pokémon from Gen I and II to Ruby/Sapphire/Emerald
- Successful trading of Pokémon from Gen II to Gen III
- How to Trade From Pokemon Red/Blue/Yellow To Omega Ruby/Alpha Sapphire
But it looks like we have the most robust version yet with Poke Transporter GB: another way to trade Gen I/II Pokémon to Gen III. Inspired by the likes of Goppier who was behind the second link in the above list, Poke Transporter GB works by amending saved files on both ends to allow the passage of Pokémon and you’ll need:
- A Game Boy/Game Boy Color
- A Game Boy Advance
- A GBA Flash Cart to put the software on OR GBA Link Cable ROM Sender which sends software to a GBA via a GameCube or Wii running Homebrew
- A Game Boy Color link cable
lost saves went through the process and it worked! And, yes, you could just use PKHeX but this is way cooler.