To be clear, when you run GB and GBC games in TWiLight Menu, they're running in an emulator. Likewise, you can run GB and GBC games in an Everdrive on a GBA Micro if you use the Goomba emulator.just read your post. twilight menu ++ (which I recommend) can play gameboy and gameboy color games by default, and it even adds color to normal gameboy games like dkc.
Running GB and GBC games without emulation on a GBA, GBA SP, or Game Boy Player requires a completely different flashcart, like the new EZ-Flash Jr or the ElCheapo SD.