User blog comment:Wrath022/Chapter 516: The Truth About Enchantment, Review/@comment-7418318-20170101085701/@comment-7418318-20170101231754

But if she can overcome Erza, Irene has all the time in the world to use both her enchantment and Wendy's healing magic to analyze the body she's in.

Sure there's no guarentee that she can figure out how the antibodies work or even locate them like you said Wrath, but there is also the chance that she can do it.

I wonder if she might try to capture all the Dragon Slayers so she can have a wider variety of samples/specimen to figure it out. ^^ No... I doubt that in the current situation that's an option for her.