User blog comment:IamJakuhoRaikoben/Chapter 468: Memory of the Stars, Review./@comment-5894890-20160109223702/@comment-7418318-20160109232650

But that there isn't such a "Oh no, I'm on the wrong side of the war!" moment has it's charms too.

True, Brandish lost her reason to kill Lucy for personal matters, but her faith/loyalty/whatever-makes-her-follow-Zeref didn't really take a hit here. For all we know she's still fully loyal to Zeref and Alvarez and thus an enemy of Ishgar and Fairy Tail.

Sure she's playing along for now to learn of her and her mother's past, but what will she do once she has all the information?

For startes, she's witnessing one of FT's strongest fighters being taken out of the fight for the time being. That knowledge could be a tide-turner for the war if she manages to slip away.

Brandish already tricked Lucy even when Lucy had far less reason to trust Brandish, so now with this apparent friendship forming, it'd be a piece of cake turn the situation around in a way that allows Brandish to slip out of the guild and make a run toward her own lines.