He's a lot like Pesce in terms of his dzone coverage IMHO. Biggest thing he needs is more confidence and he'll get that as he grows as a pro.
I say this with admittedly limited viewings of Fleury, so take it with a big grain of salt. One thing I have seen, since day 1, with both Pesce and Slavin is they have almost zero hesitation in their game. They quickly make a decision and act or react. They aren't always right, but more often than not, they are, and it's the ability to think quickly and make a decision that, IMO, is one of their strengths. It seems to come naturally to them and makes them much more aggressive as well. Granted, I didn't start seeing much of those guys until they were 20/21, but still, that to me is something that comes isn't as much learned as it is instinctual. Even Hanifin, who makes his share of mistakes (which I attribute to youth), doesn't hesitate. He makes a decision and goes with it. Ryan Murphy on the other hand is the opposite. He looks like he plays scared, hesitates often, and looks very unsure of himself.
Fleury has all the physical tools of those guys (Pesce/Slavin), and frankly, maybe more. My concern (again in the limited viewings I've seen) is the hesitation in making plays/decisions and because of that, he seems more conservative in his play. Maybe for him, like you said, it's a confidence thing and maybe it's a case where he just takes longer to get accustomed to the speed of the game before allowing his skills to come into play naturally. If he can do that, I see no reason why he can't be a LHD version of Pesce.