I wouldn't go around saying it, bu I am one of the biggest GameBoy "gurus" around. I've written quite a bit about the GB/SGB/GBC library and know it quite well.

To answer your question, any GBC game that has a black cartridge is also SGB compatible. This includes all GBC launch titles as well as titles released up to mid-1999. Those clear shell GBC games tend to almost always be GBC-only games, dropping support for the SGB entirely. There are a handful of exceptions though, like Dragon Quest/Warrior Monsters 2.

Interestingly there are a couple games from around late 1997 that saw BOTH a SGB release and a GBC release. Wario Land 2 springs to mind. One cart is gray, one cart is black. Yet both carts will run the same SGB mode if put in a SGB1 or SGB2.