well there are three known Earthworm Jim games so far:
Earthworm Jim 2, a port of EWJ2 developed by Super Game
Earthworm Jim 2 aka Earthworm Jim 4, a port of EWJ2 developed by
some people who used to work for Sachen and seemingly published by Shin-Shin/K and later by NT (Ka Sheng)
Earthworm Jim 3, a port of EWJ1 developed by Hummer Team & published by NT
then there's Happy Biqi, a clone of EWJ2 made by Waixing around 1997 or so - it's believed to have had a cart release around that time, but no cart has been found AFAIK.
Recently though (from around the mid-2000s) it has turned up on several plug & play consoles made by Subor - the current ROM originates from a download site run by Subor providing games to play on some of their 32-bit consoles equipped with SD cart slots & NES emulation. You can find that ROM
here.
Most plug & plays have an English version of the game just called "Happy Biqi: World Fighter", the ROM is the only known version called "Happy Biqi 3" and aside from being Chinese it appears to be identical. So chances are Happy Biqi and Happy Biqi 3 are the same thing, and there was never a Happy Biqi 2...
an Earthworm Jim version of this game may or may not actually exist, but a game has been spotted on old Waixing game lists called "Earthworm 3" or similar (in Chinese), so it's possible.