Requirements

Given this tutorial is about receiving gifts from language restricted routes, it will assume that your 2 games will have different languages.


1. A Pokéwalker, it doesn't matter which game + language it was originally bundled with
2. A legitimate(retail) cartridge of HeartGold or SoulSilver, with Language A (will be referred to as Game A)*
3. A legitimate(retail) cartridge of HeartGold or SoulSilver, with Language B  (will be referred to as Game B)*
4. Reached the point in both games where you can capture a Pokémon, and have it in your box.


* The reason for specifying legitimate, is because the legitimate carts has a infrared port that can communicate with the Pokéwalker.
The Pokéwalker directly communicates with the cartridge's port (not the 3DS' infrared port). Repro copies/clones do not have them.


As a side note, if you made your own dump of HeartGold/SoulSilver, and you've lost the cartridge, it is still possible to use this tutorial for you.
If you own a 3DS, what you need to do is install TWiLight Menu++, then launch the games from within TWiLight Menu++. You will need a have a legitimate(retail) NDS cartridge with a Infrared port (such as Pokémon Black, White, Black 2, White 2) in your 3DS' cart slot.