I've got an inbound Motow carrier, a couple others here on the forums have theirs already. 1) they're available now, no 1-3 month wait. 2) they're built here in the US (may or may not be important to you). 3) will easily support 2 heavy e-bikes. 4) can support a variety of wheel sizes (radius and width) as well as wheelbase length (often overlooked). 5) all stainless steel, strong! 6) doesn't require any adapters for step-thru's etc. 7) supports bikes using wheels, so mudguards fenders, rear racks are not an issue. 8) can use a 1.25" hitch and/or a 2". 9) base rack is decent price, but can also opt for a lift (mechanical or power) which will raise/lower the unit by 16" to make loading/unloading bikes much easier; adding the mechanical lift (use a drill) brings the price similar to the higher priced carriers like the Thule EasyFold XT 2 which was my first choice until finding none available and then seeing Motow. 10) they will actually talk to you and customize it to meet your needs. 11) breaks down somewhat without tools so can store/carry it easier.
I needed to support a smaller 20"x4" step thru with a wheelbase just under 44" and a 26"x4" with a wheelbase of 48". Both with fenders and both with built-on rear racks. I also wanted to be able to use both of my vehicles, my truck with a 2" receiver and my wife's car with a 1.25" aftermarket Curtis receiver (no 2" option). They don't recommend using a 1.25" to 2" converter, and as they have a 1.25" stinger option it isn't needed anyway. Weight of the rack is under 30lb, and just under 50lbs if you opt for the mechanical lift. Combined with 2 ebikes minus their batteries and I'm still well under the 200lb limit of the 1.25" hitch on the car.
Ordered a couple of days ago, will let you know how it goes once I have it. My Blackbird won't be here until November batch, so I'll be like you and using it with my wife's ebike and my regular mountain bike.
motowus.com if you're interested