Good ol' Captain (or lieutenant? Who knows this days) somehow emerged in Japan to bring impreial justice to this mongrels. Little did he knew Hanma Yujiro and Baki Hanma were going to have their schizo fight and were NOT pleased when 2.5 meters of armored gargantuan appeared in the streets.
So, we basically have several ways to go right here, lady and gentlemen:
Bakiverse can use ALL fighters at once but not nuclear bombs, of course. This includes giant fucking elephants, characters who are chronologically divergent (i.e. characters who where canonically dead by the time another character appeared can act together) and every named fighter. They fight against Titus simultaneously.
Bakiverse can use only character who are capable to fight by the time Baki and Yujiro went full schizo mode, starting with, well, Baki and Yujiro duh. Other characters can arrive to help but in realistic times (for this verse)
Titus vs Baki and Yujiro alone!
Before some cult of NUCLEAR POWERED ONE HUNDRED GAZILLION CELCIUM PLASMA PISTOLS appears I might say that I take this maddened calculations with the grain of salt. It was a Black Library book (you know, these books where Space Marines either often defeated by regular humans or can go massive FTL+, a lot of times in one book) which stated that large titan plasma cannon use a 100 million degree plasma. You know, the city block destroying weapon, yeah. You know, the mightiest non-space weapon Imperium has. Not the fucking PLASMA HAND PISTOL. So stop be ridiculous and remember that EVEN if somehow plasma pistols are throwing literally hundreds of millions degree plasma here and there it doesn't make them equal even to a small nuke.
Thus being said, try to be reasonable here. I personally think this is pretty interesting match-up so let's estimate characters somewhat logically. Yujiro IS NOT a city-buster neither is Titus. None of them is capable to FTL combat or reaction speed. To cut the story short, b-reasonble and use mid-end estimations for every combatant.