From their recent friendlies, looks like they're going to play 3-4-2-1, with De Bruyne playing very central.
A lot's going to depend then on his central midfield partner (whether it's Dembele or Witsel.....or more unlikely Fellaini). If they're not up to it (and I have my doubts), there's a danger they get bullied in there by some of the other tournament favourites.
I'm still predicting that they'll win the group, thump someone from Group H in the last sixteen, and then go out meekly to Brazil in the Quarters.