The last I hards was in the "Year Ahead" where they mentioned it after discussing the TG and DB DLCs for Q1 and Q2...

Longer term, expect to see information about systems like a character customization shop so you can change your character's gender, appearance, name, etc., player housing, and other systems that we'll announce in the future. We'll have much more information about all of these as the year progresses.

So from that I gather it will soonest come with the Q3 DLC...
...which would be a shame, since it'd have fit sooo well with DB. I mean... assassins whose face has become too well known and plastered on every corner per wanted poster needing some "plastic sorcery" to change their looks? Wherever would character recustomization make more sense? (and of course race change would have to come hand-in-hand, or in the wake of appereance recustomization)
I really wished they would not wait until after DB, but give us recustomization...
Sooner! Sooner! Sooner!

When your old and grey. Like me. I'll probably be in the ground before it happens