I'm not familiar with the SNES classic, but on other platforms, you need to use a Retroarch core which supports Super Game Boy emulation. Same Boy and BGB do, while Gambatte doesn't. Gambatte lets you use the "GBC colors"... but they aren't true colors.
See this video:
Game Boy games aren't always better on the Game Boy Player. Pokémon Red and Blue are two great examples.The Game Boy Player ignores all the Super Game Boy co...
www.youtube.com
The Game Boy Player (which behaves like a GBC) applies a generic palette to the game. Every still object is red, everything that moves is green. The Pokémons in battle don't have a specific color - they are all red.
The Super Game Boy one is a true colorization (albeit very basic). The game has a built-in palette and the Super Game Boy "knows" to change colors when you enter a new area, or for the various Pokémons while in battle.
Here you can read an excellent article on the SGB.
The GBC is better for games including a native GBC mode (that is, cross-gen GB/GBC games, which usually came in black cartridges, as opposed to the standard grey cartridges). Like Pokémon Yellow, Gold and Silver. They were developed with the GBC in mind.
Here's a comparison of the Pokémon Gold intro on the Game Boy Player and the Super Game Boy 2. I did this mostly to compare the colors difference.I had to ed...
www.youtube.com
By the way, you should try this hack. It converts the game into a GBC game, with a true colorization
This is a colorization hack of Pokemon Red and Blue, done entirely using ASM. It takes full advantag
www.romhacking.net