Though it was completely shocking and came so soon, Irene taking over Wendy's body was a bit too early. Irene barely fought Wendy and Erza before possessing Wendy. I'd rather prefer they have a longer battle but I guess this will do.
I also wish they wrote this better too. Instead of possessing Wendy, it would be better to have Irene switch bodies, have Erza realize she horribly injured Wendy while she was in Irene's body then end the chapter there. Though in my prediction, it would make sense why they wrote to possess Wendy's body rather than switch them.
Prediction:
Irene is a dragon but was put back into a human body by Zeref. I'm sure Erza and Wendy's feelings will reach each other, thus forcing Irene out. But since Irene's human container is practically destroyed, she won't be able to return to her body, which forces her to become a dragon again. Then they battle her with the remaining dragon slayers since there's really no spriggans left for them to be stopped. A battle will ensue, which will make it easier for Acnologia to return since he can smell all the dragon slayers and an actual dragon in one spot. (seriously, where the fuck is he?)
I really do hope she becomes a dragon again. No way in hell they made her a dragon just so we can feel bad for her. They better use her as a dragon otherwise the writing is going to piss me off again. And if she does become a dragon, that makes it easier for Acnologia to return.
One can only hope.
3/5- Other than the body possession, this was an extremely underwhelming chapter. I was hoping for the typical "battle of attrition" Erza fight with Irene but we got this instead. It could be worse, but it definitely could be better.