We have 2 RadMini ebikes and use Thule Apex Swing 4 bike carrier. The carrier itself weights 37.5 lb and can carry up to 4 bicycles with total weight capacity of 150 lb. Each ebike weights 67 lb. When we go on the trip I do remove the batteries (7 lb each) so I still have 30 lb to spare which allows me to put 2 more regular bikes on the bike rack for my boys. And yes, we need to use bike carrier bar for the RadMini step-thru ebike. We are using this setup for last 2 years and it works well for us.
I just learned about another interesting product by 1up. It looks like this carrier can handle up to 225 lb of weight or 3 ebikes.
https://www.1up-usa.com/