In the last year, I've seen someone mod the GBA link cable to be cross-compatible with gen 2 Pokemon games with gen 3 pokemon games (proper GB to GBA connectivity, which was never officially offered), so such a feature should totally be feasible I would imagine considering the GameCube can connect with a GBA. But an official one doesn't exist, so not only would you have to troubleshoot such a device all on your own, you'd also have to properly develop some sort of GameCube testing homebrew that could connect with your GB to ensure everything is working properly to begin with.