You'd be hard-pressed to find a game like UFC Undisputed on the PC, no less in MMORPG form. PC games generally struggle in any department that isn't FPS, RTS and fantasy/sci-fi based MMORPG's. It has the occasional good single player RPG as well lol, like the Baldur's Gate series, Fallout, etc.
Your best bet, if you don't care about graphics whatsoever, would be to go after one of the 100's of boxing/martial arts browser based games out there. Very few of them actually have graphics (they're like manager sims, you control the stats and their career, but none of the actual fighting)... but I guess you probably build up a fighter and send your creation out to fight others and stuff.
Here is an update for MMA, UFC MMORGP - new game launched in 2013 called Absolute Champion. Here is a link: www.absolutechampion.com . In the game you can choose your fighting style (10 styles available) and choose your body type, skin tone, head and etc. Once you create fighter you can fight vs other fighters in 1 vs 1 or big tournaments.
Game is turn based strategy and more about tactics and stats, but its fun. But you can see the fight and run you strategy in attack and defense.
Each fight has 3 rounds and you can win with knockout or by points.