The Lord Yuan Shu community has discovered two mods for Destiny of an Emperor II, which let you play as either Wei or Wu (thanks to thechieftain for finding them). To play them, you need to get a copy of the Japanese ROM of DOAE2 (Kongming's Archives has a copy) and a patching program such as SNES Tool. Patch the ips on the ROM file and you can play the mod.
Here are the links:
Wei: http://wild-plants.hp.infoseek.co.jp/patch/sougi2.zip
Wu: http://wild-plants.hp.infoseek.co.jp/patch/songo2.zip
Samuel, a board member of our forums, has been kind enough to supply us with a guide for the Wei mod. Check that one out too.
Here is Samuel's guide for the Wu mod. Chapter 1: Dong Zhuo and the Rise of the Sun Clan Sun Jian stands in front of the Han Emperor, who commands him to conquer rebel lord Dong Zhuo’s general Hua Xiong. Cao Cao is beside the emperor. Sun Jian speaks to him but Cao Cao says that he is too busy. He cannot fight Dong Zhuo and does not even lend his two generals.
Thanks Samuel for the guides on these Wei and Wu mods, there is very little information out on these games.