You asked

Sigma 35mm f 1 4 dg hsm art vs sony fe 35mm f 1 4 gm?

Here is what the site says about that.

From Sigma 35mm f/1.4 DG HSM Art: Sigma 35mm f/1.4 DG HSM Art: A prime lens by Sigma for Full frame cameras, 35mm f/1.4. The 2012 lens that started Sigma's Art line; common and cheap used. Specs - Maker: Sigma - Focal length: 35mm (prime) - Maximum aperture: f/1.4 - Made for: Full frame sensors - Mounts: Canon EF, Nikon F, Pentax K, Sony E, L-Mount - Stabilised: no - Autofocus: yes What it frames like - On full frame (Canon EF, Nikon ...

From Sony FE 35mm f/1.4 GM: Sony FE 35mm f/1.4 GM: A prime lens by Sony for Full frame cameras, 35mm f/1.4. Specs - Maker: Sony - Focal length: 35mm (prime) - Maximum aperture: f/1.4 - Made for: Full frame sensors - Mounts: Sony E - Stabilised: no - Autofocus: yes What it frames like - On full frame (Sony E): as marked, 35mm. - On APS-C (Sony E): like 52mm on full frame; f/1.4 gives about the depth of field ...

Quoted from this site's pages.

From these pages