>>25304734Game Boy games without GBC games, when played on the GBC, could do the color thing. International Yellow and Gen 2 have GBC features so they couldn't, but Red, Green Blue, and JP Yellow (the color features were only added in the international release) could.
That being said, none of the VC games can do that. Even some VC releases with color features like Wario Land 2 are stuck in monochrome with no way to change the palette besides gray or green.
It's funny because the homebrew GB emulator I have on my 3DS changes palettes just fine.