That is exactly like the roof on our house, roll formed on site. Fasteners are hidden within the standing seams.

However, done this way, there will be condensation on the underside. Our roof has plywood and then a vapor barrier underlayment.

How do I know this will have condensation? I have 4 outbuildings built pretty much this same way, sheet roofing without vapor barrier. Moisture is a huge problem, it literally rains inside the buildings...