So, I just applied the last rank 3 essence after collecting all of the Sparks of Unwavering Strength, and this achievement did not trigger. I’ve got a level 87 neck, a rank 4 essence, and 3 rank 3 essences. Needless to say, all essence slots are unlocked. Has this happened to anyone else?
EDIT: This achievement triggered next time I logged in. Just a heads up in case this happens to anyone else.