PC version Fans have made a PC version. Some are still early, so read the project page first.
Fans took Gundam SEED: Battle Assault apart and rebuilt it so it runs natively on a computer, often with widescreen, higher frame rates and mods. Here is the project we know about:
A fan-made recompilation of Gundam SEED: Battle Assault for Game Boy Advance. Requires the user's own legally obtained ROM. No copyrighted ROM or game assets are included. Supports fullscreen with Alt+Enter, keyboard controls, and community