Welcome!
Needed signing and makes sense. I was not sure a few weeks ago due to his age and cost. But it is a short-term solution and provides less pressure on Bentancur (spelling?), who I still hope will be given a start every now and then. Similar to Pogba's first season. It also gives time for our other prospects to develop elsewhere and come back in two years when Matuidi is likely stepping back to Ligue 1. We need a DM who can win and recycle the ball, protect Pjanic if he plays, and so forth. I also like having him as a B2B. If we move to three-man midfield I can easily see Marchisio playing in a deeper role with Matuidi and Pjanic in front. Actually, that sounds quite good!
Unfortunately Pjanic is not good passing forward, maybe he doesn't have a good chemistry with Higuain and Dybala, I don't know, but he seems more focused at the regista role, connecting the defense with the midfield and side pass to other midfielders. He is prolly tasked to replace Bonucci's role.
The problem lies ahead of him, this is what we lack, the man who goes the midfield with the frontline.
Obviously Dybala is not cut for this, he either plays to deep and far away for the killer pass he is capable off, or too front, isolated, like Higuain.
We need a player with dedicated skills for that job, at least for a sub to Dybala, untill the later masters this role. A sub is always needed when we face injuries and suspensions and no other player in our lot can replace Dybala when needed in this role. This is the kind of the tool we lack the most!
Matuidi adds nothing we already didn't have...