A new rumor has started circulating that Game Boy and Game Boy Color titles will soon be appearing on the Nintendo Switch Online service. Two separate sources have claimed that one of four emulators found in datamined NES source code will be utilized to bring Game Boy and Game Boy Color games to NSO subscribers.
https://www.notebookcheck.net/Game-Boy-and-Game-Boy-Color-titles-may-show-up-on-Nintendo-Switch-Online-soon.558125.0.html