You can, but there wouldn't be much point unless its a hardy variety of fuchsia - the half hardy ones need either to be removed to a greenhouse or similar, or binned.

I reckon its a bit late for it to make decent roots before the ground cools down. The benchmark is usually end of July for planting out hardy varieties....to be on the safe side.

That may or may not be so, Amblealice, but better in the ground than out - fuchsias are sensitive to frost through their roots, and are therefore more vulnerable in a pot.