So i finnally know how vincent's limit break are working, i know many ppl said even by deleting vincent's IA his limit break canot be controlled, there is a way to control vincent limit break and even modify the monster who he will be.
The LIBRE program is not the key, this program just modify the " effect" of the limit break, when i say effet i mean the boost stats for example, and the fact vincent because incontrollable, but the fact he disapear and transform into a monster is not modified by LIBRE, since its not in the same file , when vincent transform himself its an " animation" so its a value in his model battle : VINSENT.LZS , on the animation section,an animation called " AC 00" , 00 make him into gallean beast. 02 into death gigas ( or big gigas i dont remember the name) etc, to summarize , by copying vincent's limit break animation values in his battle file, and put it into any other character, i can have cloud transforming into chaos and control him.
Using this method i can have finnally what i was looking for, giving to sephiroth his own limit break, transforming him into a bizzaro's or safer sephiroth, and control him, its working, but now i need to find the values of the animation " transform " of cait sith who make everyone disapear ( like i said i canot transform into a big enemy like safer or bizzaro sephiroth if my two other characters are still in the battle, cait sith limit break can " erase them"), so i'll make a special limit break using the "transform " animation of caitsith combined with the "transform "animation of vincent If im right the result will be just like ff10 summon system.