All you do is buy the Analyzer force metal, attach to anyone of your characters that is in your party that is fighting. When their turn comes up, just hit the triangle button and go down to the analyze option.

Buy the Analyzer Force Metal (1000 Zenny) from Jasmine, after defeating two Preon Chaser
in Chapter 2, equip it on X, then engage a battle against any enemy, open the menu with
triangle button and you'll see the Analyze option available.