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Biria. They're among the few making true easy boarding, low entry step-through frames. Listed weight varies from around 33 lbs on up, with the e-bikes weighing closer to 40 lbs or more.
Most other bikes advertised as "step-through" are actually mixte and compact frames with sloping top tubes. I've also seen a few folding bikes with step-through frames, notably by Tern a few years ago.
Keep in mind that a step-through or any upright bike will be less efficient for climbing. Sitting upright is comfortable for reasonably short distance/duration rides, but makes less efficient use of the adductor muscles. An ideal upright/step-through bike would have motor pedal assist for climbs.
I'm not sure disc brakes would offer any real advantage for the relatively leisurely pace of upright bikes used on pavement and groomed fine gravel/chat trails common to most cycling infrastructure, multi-use paths, etc. Good quality, properly adjusted rim brakes work very well.
FWIW, I went through this back around 2015 when I first got back into cycling after a long hiatus and recovery from a 2001 accident that fractured my neck and back. I needed a cane to walk any distance until 2014. When I resumed cycling I started with a 30+ lb Globe Carmel upright comfort hybrid, and still occasionally used it for errands until around 2019, but haven't ridden it since. Over time with plenty of physical therapy I was able to switch to a more efficient hybrid and, by 2018, mostly drop bar road bikes. But it's a constant struggle and if I take much time off from cycling it takes awhile to regain the strength and flexibility to comfortably ride a drop bar road bike. I expect I'll eventually switch to a hybrid e-assist bike.