Longer answer; Based on my limited 'steep hill' riding.
My normal 'get some fresh air' ride of 13 miles ends with a 0.6 mile hill at about 8.5% grade.
eBike does just fine. I use PAS-5 and low-end gearing. Climb hill between 7 & 10 MPH depending on how hard I pedal. Have always remained in the seat and pedal at about the same rate as when on level ground. eBike could go faster as there is lots of power reserve I'm just comfort at the described rate
. . . no need to break into a sweat . . .
Elevation data from Google Map Bike directions.
Of course PAS-5 & low gearing can quickly reduce battery range if your travels have several of those steep hills.
She ran really low on battery climbing the last of the hills, shown here:
And it was a struggle for her. That said, this was after 23.6 miles of challenging ride. She had to reduce PAS in order to ration it to complete the rest of the ride, since when the battery is dead it's really hard to pedal even on the flats. I was on a Luna Apollo and had plenty of power and battery, but that's a different kind of bike, and more expensive.
Not everyone wants to do rides like these, especially on an upright step-through frame. I concur with @MuttonChops that the bike can handle the hills, but range is reduced.
PS: She is now on a Luna Apollo as well, on which I've replaced the stem and handlebars to give up an upright riding position. Not a step-thru, but full suspension is nicer than even the Kinekt suspension seatpost.