There are hundreds of Titles in this game, most of which are found by completing the Trials for each character while the rest are gained by completing the Arcade with each character on the Hardest difficulty and by performing certain moves (e.g. Technicals, Reversals, Counter Strikes, etc.) in ONLINE matches.
Some of these do stack such as the Titles for beating arcade on any difficulty and the Hardest with each character.
For a full list, click on the below link for more of a detailed breakdown on all of them and their requirements.
https://www.xboxachievements.com/forum/topic/205917-requirem...