This is how I got all my titles also I'll apologize now if my words are confusing or wrong, English is my 2nd language.
I played versus with a second controller by myself and I picked scramble stage with normal health, 1 round, unlimited time. Picked the same characters, used the player 2 controller to figure out a combo to finish with a power blow, did it with player 1 power blowing them into cliff hanger and did a grab. Did rematch did the same thing and choose to do a strike instead of a grab.
Doing these will give you these titles: the Newbie, Power Blow, Power Blow After Critical Burst, Cliff Hanger w/ Grab, Cliff Hanger w/ Strike title for each character which is a total of 110. You should get more titles for 100 Versus Matches, 100 Critical Bursts, 100 Power Blows, 100 Cliff Hangers, and a few other things.
For costumes, I did Rookie and Easy tag matches for both Arcade and Time Attack for every character. You will unlock 4 costumes total for that character few have more costumes but most have less. Note only the first character you pick will receive the costume and not both characters on your team. Reason I did tag matches is because its only 5 matches, 1 round, and less load times. This should give you 4 titles for both Arcade/Time Attack Tag get more for harder difficulty or solo mode.
So after this you should have at least 19 titles for getting all the costumes for almost all the characters (I excluded Tina, Lisa, and Christie's title because of the Legendary Difficulty Costumes). You will also get a few titles for doing a certain thing 100 times.
Playing the game automatically gives you 27 titles.
Doing command training for every character will get you 22 titles.
Story mode gives you 20 titles.
Story mode missions is a total of 62 titles.
Minimum Total Amount:
Versus Mode = 110
Arcade/Time Attack Tag = 4
Costume Titles = 19
Playing DOA5 = 27
Command Training = 22
Story Mode = 20
Story Missions = 62
Total 264 Titles Minimum
Please note that I did not include other titles like landing 100 (Power Blows, Critical Bursts, Taunts, etc.) which you should get from doing Versus mode or normally playing, playing a character 50+ times, playing Arcade/Time Attack on Solo or a higher difficulty, playing online, and winning matches.