With Matic and Lukaku significantly changing the attacking dynamics of our game, regardless of the formation we play, I believe Jose would set up more offensively than last season.
Formation is just one part of the system, ie it can be set up offensively/defensively for a 4-3-3.
Regardless of us playing 4-2-3-1 or 4-3-3, we should go all out and attack. Specifically, in a 4-3-3, Pogba-Herrera should have more freedom to join the attack.
So I think the key things to watch, not just in this game, but also in the upcoming matches......
1. Matic & Lukaku changing the dynamics of our attack
2. With the new dynamics, Jose could set up more offensively than last season
3. The 2 factors above to positively affect the performance and confidence of our players, especially our main attackers of Martial/Rashford/Mkhi/Mata and Pogba. Last season, I think the underperformance of our attackers was not only on the individual level, but also partly because Jose set up defensively, hence negatively affecting their performance and confidence, making our attack very predictable, congested in the middle without much width, etc......
4. A more consistent starting XI than last season. This would help build up our team chemistry, which is a very important factor that often "ignored" by most people here
5. Build up momentum, for both performance and confidence level, especially in the upcoming easy fixtures until October
(Some of the main factors that Barca and Real have had huge success of late include consistent starting XI, momentum/team chemistry, etc....ie their core players have been playing together for the past few years. It's not just about Messi/Neymar/Ronaldo/bale.)