I've watched most of Zadina's games this season.
He is excellent on his edges. The reason people such as Steve Kournianos and Sam Cosentino have made comparisons to Nico Hischier is primarily his ability to turn on a dime and control his motion in tight spaces with ease and precision.
That said, beyond that and their shared association with the Halifax Mooseheads, Zadina and Hischier are very different players.
Hischier's greatest attribute is his hockey IQ; while he tends to play a roaming, patient game, he always takes advantage of his quick acceleration and attacks the puck whenever he sees an opportunity to strike. He is fearless as well as aggressive, and he actively pressures the opposition on the forecheck. There is a sense of relentlessness in his game, and he hustles to get to loose pucks. He drives his line and knows when to hold on to the puck, when to pass the puck, and when to shoot.
Zadina is a much different player. He tends to let the play come to him, and he does not move his feet anywhere near as much as Hischier. There has been a lot of half-speed coasting in the games so far, and when his teammates don't have possession of the puck, he can have some fairly quiet shifts; when there are loose pucks, he is just late enough that the opponent gets to it first; rather than lay a hit and fight for possession, he sometimes just turns away. He has the ability to challenge the opposition and pressure them, but he does not do this as effectively as Hischier for two reasons: he lacks a little bit of the same explosiveness, and he also does not assess plays with the same keen eye or edge as Hischier. His ability to read plays is a notch below that of the Swiss star. In the defensive end, he has an itch to leave the zone early at times and is sometimes prone to turning the puck over with a bad pass or holding on to the puck too long. There was one play against the Screaming Eagles, for example, where he tried to wind up from behind his own net and tried to beat the opposing forechecker, but instead turned it over and created a bit of havoc in his own zone.
His offensive skill set is quite impressive, and there are some who would contend that he has the best hands in the draft, although I think that point is debatable. His ability to weave around using his edges makes his body difficult to pinpoint when he wants to hang on to the puck and deke around the opponent; purely from a stick-handling perspective, I think Andrei Svechnikov is better at handling the puck from a standstill, although Zadina's ability to swivel and swerve around the opponent while keeping the puck makes him very slick in a different manner. Unlike players like Patrick Kane and Casey Mittelstadt who do quite a bit of stick-handling while standing still, Zadina's handling of a puck is more like Hischier's in the sense that his skating is as important, if not more important than his hands whenever he makes a one-on-one move against the opposition. At 6'1'', 192 lbs, he has the strength and balance to keep the opponent off of him when he has possession of the puck, but I haven't seen a lot of physicality from him on the forecheck, and sometimes he'll let his teammates dig for the puck while he waits a few feet away in open ice. He isn't afraid to go to the front of the net or to go into high-traffic areas, and he knows how to maneuver into open space in the crease or anywhere where there is space between the opponent and the puck, but he also doesn't push hard enough to win a lot of battles; he has a tendency to do too much standing around when teams are trying to fight for a loose puck. Unlike Hischier, who is 10 to 15 lbs lighter, he doesn't push hard enough -- he doesn't jam the net hard enough or compete with anywhere near the same intensity or determination.
He is a shooter. He doesn't have a world-class shot, but he loves to put the puck on net and has a tendency to cut into the middle to change his shooting angle, holding on until he sees something; he can also distribute the puck, but as I mentioned, he sometimes makes errant passes that result in turnovers. While he is skilled, he makes questionable decisions with defensive consequences; that has to be fixed before teams will ever trust him at the NHL level. Based on his current play, he isn't NHL-ready from a defensive point of view. Last year's draft had a plethora of high-end, two-way players; a few of those players were NHL-ready from a defensive point of view. At the moment, Zadina is a thoroughly one-way player who has to clean up his game quite a bit.
Zadina started the year on a line with Arnaud Durandeau and Raphael Lavoie. Ever since Otto Somppi's return against Cape Breton five games ago on October 13, 2017, Zadina has been lined up alongside Somppi and Durandeau.
The presence of Somppi, who is a lightning-fast, skilled line driver has had a very positive impact on Zadina. The right half-wall tends to be where Zadina operates from.