I'm an ACC denizen so I'll look at this from ND's perspective:
UNC lost wing Kennedy Todd-Williams and guard/forward Destiny Adams to the portal (and Mississippi, Rutgers, respectively) and Eva Hodgson to eligibility. Paulina Paris and Kayla McPherson -- dynamic offensive players but slightly smaller guards -- were coming back to join Deja Kelly in the backcourt, but Coach Courtney Banghart probably felt she needed a taller guard/wing. Hence, 6'0" Donarski, who averaged some 13 ppg for the Cyclones, will join. She was also Big 12 defensive player of the year in 2021-22, which will help.
Donarski doesn't need the ball much, which will also help because Kelly controls the ball in crunch time.
I respected Todd-Williams who I thought was a physical and effective player against ND. While Banghart has found a very good replacement for the Tar Heels in Donarski, I still like Sonia Citron not having to play against the physical Todd-Williams. And now, Coach Ivey can unleash the very tall Cass Prosper (remember, no Adams coming back) and physical KK Bransford on Kelly.
Donarski's three-pt. shooting has gone down since she was a frosh on an ISU team that shot tons of three's. If she can get her pct. up a bit, UNC will be an outside team to cover. A lot. (Paris really came on last year as a frosh.).
We'll see if that makes up for the loss of Todd-Williams.