Chinese website CNMO today posted a sketch that allegedly reveals the design of the P9: we can see a pretty thin body, rounded corners, a physical home screen button, and a dual rear camera. This design kind of reminds us of the HTC A9 (especially because of the rounded corners and the home button).
It would be quite unusual for Huawei to launch a handset with a physical home button. However, we did hear that the P9 would come with a new design, so perhaps we shouldn't be that surprised if it ends up looking like in the image below. It's said that the P9 will be the first in the P series to feature a fingerprint scanner, and maybe that's one of the reasons why the home button is there. Of course, Huawei could also embed the fingerprint scanner on the back of the device, just like it's done on the Mate 8, Mate S, G8, and others.
Like the P8 before it, the Huawei P9 might sport a 5.2-inch display. The smartphone should be powered by an octa-core Kirin 950 processor, also offering 4 GB of RAM, and a 3000 mAh battery. As for its dual rear camera, this could be a 12 MP one. A recent rumor had it that the P9 would have 6 GB of RAM, but that's probably not true (according to the same rumor, the handset should've been announced earlier this month at CES 2016 - which obviously didn't happen).
source: CNMO (translated)