The Sigma 16mm f/1.4 lens for Sony e-mount was released late November 2017, one thing stands out very boldly in any review, talk or examples on this lens in the year plus since its creation and that is its sharpness.
Sigma 16mm at f/1.4 blows the Sony 16-50mm kit lens away and makes the Sony 16mm f/2.8 prime lens look soft. Both those lenses are native yet the Sigma 16mm matches them for auto focus and for one last time….is sharper.
The Sigma 16mm does not have OSS (Optical steady shot) meaning unless you have IBIS (Inbody stabilization as the a6500 has) your video and slow shutter speed photos may be at risk of quality degradation.
The lens is a landscape beast, highly capable for low light and night use due to its very very open f/1.4 aperture. One thing to note is the autofocus noise can and will be picked up by the camera body mic indoors.
I left my SELP 18-105mm f/4 behind and took the Sigma 16mm out on a sunny day. Here are images taken on the Sony a6500 with Sigma 16mm f/1.4 lens, most images are cropped followed by a further cropped image to show the detail.