I played a little with it on a game boy pocket when I was younger, so I don’t remember too much but I have seen videos of people playing it on the super game boy and my opinion is it’s a bit laggy, though it could just be the low quality screen of the og game boy (or pocket) or my memory being off or both, but considering the original game boy was roughly 10 years old at the time of gen 2s release, combined with the game boy color being slightly more powerful, and crystal coming out less than a year later and not working with the original game boy (and likely gen 2 being delayed specifically to make it work better for gbc) my guess is gold/silver push the og game boy to its limits, so the gameplay is laggy compared to being on the game boy color, also with its lower quality screen, you couldn’t really see much anyway, like shiny Pokemon, or other minor details.
in short, it works, but barely.