Category:Lists of licensed ROM images
To go on these lists, the ROM has only has to be licensed by a game rights holder, not by the console rights holder. Doesn't include homebrew - only commercial ROMs or ROMs related to commercial games.
Todo: I've left out games that have lots of ports so are unlikely to be emulations, but these should still be checked.
The remake of Makai Toushi Saga on the Wonder Swan contains the original Game Boy version, which was released in the US as The Final Fantasy Legend. Hokuto ga Gotoku has a Master System that survived the nuclear apocalypse with a copy of Fist of the North Star, which had been released overseas as Black Belt.
To investigate [Switch]:
found an interesting gem 70010000016000 010041800C9A0000 [ 2001 : Download Only ] [ JPN ] [ unsearchable ] サーガイア（ゲームボーイ版） 2019-02-28 55 MB apparently according to japanese gaming forums this title has a custom made Game Boy (DMG) emulator unfortunately it was only released as an eshop download code as a preorder bonus for people who purchased the Darius collection from Amazon on PrimeDay last year.
PS4 final fantasy: https://twitter.com/manfightdragon/status/1248540935631196160
evercade cartridges probably have emulated ROMs on them
"Project Egg" has licensed PC ports/emulations of retro games https://gist.github.com/einstein95/94a03ea50d9122e08db0ad33154ba048
there was a similar project for the west, formerly at woomb.net, maybe discontinued now? might have been from the same company as project egg
upcoming: Collection of SaGa: Final Fantasy Legend
Neo Geo Mini
Namco Museum Archives Vol. 1
amco Museum Collection 1 (cartridge released for the Evercade handheld)
au Smart Pass Premium Classic Game (a Japanese mobile service)
PicoPico (another Japanese mobile service service, but seems to be iOS-only)