May or may not be up to the task, but it's only a phone call to find out - https://parkit360.com.au/collections/models-pricing/products/p360hd-4535kg-boat-caravan-mover They're not far from you, so may be able to arrange a site inspection?
They have a few options for power, and can be set up with a brake controller to work the trailer brakes. Bloody expensive though, but they appear to a fair bit better than the average power mover.
I think 1 in 10 is about on their limit, and the driveway in the photo looks steeper than that? Don't measure the amount of fall over the entire length of the driveway, measure it over just the steepest section so you have a true idea of the hill you need to climb.