Here's why:
* Different connectivity protocols: The Game Boy Advance-GameCube link cable uses a different communication protocol than the one required for Pokemon games. Pokemon games use their own proprietary wireless communication system for trading and battling.
* No Pokemon games support the cable: While the Game Boy Advance-GameCube link cable allows you to play GameCube games with Game Boy Advance games, no Pokemon games on either platform utilize this cable for connectivity.
What can you use to connect Game Boy Advance and GameCube for Pokemon games?
* Wireless Adapter (GBA): The Game Boy Advance Wireless Adapter allows you to connect two Game Boy Advance systems together wirelessly to trade and battle in Pokemon games.
* Game Boy Advance SP (built-in wireless): The Game Boy Advance SP models have built-in wireless connectivity, so you can connect to other Game Boy Advance systems for Pokemon games.
* Nintendo DS and later: The Nintendo DS, Nintendo DSi, and Nintendo 3DS consoles all feature wireless connectivity and allow you to trade and battle Pokemon using their built-in features.
Important Note: The original Game Boy Advance does not have built-in wireless capabilities, so you'll need the wireless adapter to connect to other GBA systems for Pokemon games.