Note: the hollywood rack is recommended by Rad in the US. (80lbs per bike): https://hollywoodracks.com/products/sport-rider-fat-tire-electric-bike-hitch-rack?variant=31833680609349

Also needs an adapter for 20" wheels - https://hollywoodracks.com/products/small-wheel-adapter-for-universal-wheel-holders?variant=31793946165317

Or some folks in the EBR forums mentioned this Fultyme rack - https://electricbikereview.com/forums/threads/mini-review-of-fultyme-e-bike-hitch-mount-2-bike-rack-200-lbs-capacity.39262/