Do you have the stupid little automatic 50mm ball they do or a hitch receiver? Here in Oz the new Defender comes with a 50mm steel box hitch receiver and I just put a long hitch in there and used my regular Thule rack. That wouldn’t work on the auto 50mm ball though.
I highly recommend the Kuat NV 2.0 rack if you have a real hitch receiver. It is very well made and secure. Rated to 120lbs (55kgs)
Holds our two e-mtbs with very little bounce or wiggle even on dirt roads. Real good clearance to spare tire. The hold down fits over the front wheel and is adjustable from 20" to 29" wheels, so works with any frame. Avoid the racks that grab the frame like the Thule Easy-Fold, we bought one of those first and returned because we couldn't get a firm / safe grip on the bikes.
You can also buy an extension for another two bikes. Rack folds up when not needed and there are accessories available like loading ramp and a work stand that attaches to the rack for field work.
If you fit a spacer between the tow ball and mounting plate it allows most bike
carriers to clear the spare wheel. (Defender is parked on a sloping drive which is why the towing bracket doesn't look straight)