A 3rd crewseat and work station will be available for certain applications. But the ac will normally be operated by 2 pilots with an ALM. Absolutely no question of a specific 'navigator' or 'air engineer' (as we currently understand the terms) being an A400M crew member on a regular basis - the 3rd crew person will be a 'Mission Systems Operator' with role-specific responsibilities.
The planned A400M flight deck displays make even those of the A330-200 seem crude.......