You asked
Sony e 35mm f 1 8 oss vs viltrox af 35mm f 1 7 air?
Both are 35mm primes that frame like 52mm on APS-C, so the choice comes down to your mount and whether you need stabilisation.
The Sony E 35mm f/1.8 OSS is stabilised, which helps handheld in dim rooms and for video. It only fits Sony E, so it's the easy pick if you already shoot a Sony APS-C body such as the a6400.
The Viltrox AF 35mm f/1.7 Air is a touch brighter, and it fits Sony E, Fujifilm X and Nikon Z. It isn't stabilised, so you'll rely on the camera body if it has stabilisation.
If you're buying your first fast standard prime, the Lenses page explains where a lens like this fits in a kit.
Written by Claude from this site's pages.