Question about Sigma 50mm f/1.4 DG HSM ART, Sony A

Sigma has only 4 E-mount lenses, all for crop sensors (APS-C). I recommend the Sigma MC-11 adapter Canon EF/S to Sony E-mount, then you can also use those Sigma lenses (and Canon lenses) on the A7 II (or even on a NEX-6, and and and ...) for which there are no Sony mount variants. Otherwise use the A-mount lenses on E-mount with the LA-EA3 from Sony, but if you don't have a Sony A-mount camera, I would take the Sigma-Canon variant with MC-11, many lenses to choose from (also Tamron, for example, or Canon) and if you ever want to sell them, with Canon EF/S mount you have much better chances than with Sony A-mount. There are already a few tests online for the MC-11 with "non art" lenses from Sigma, that seems to work wonderfully.
Have fun with the release.

PS: I have the Sigma 24-105 Art with the adapter on the A7, works great (also works very well on my old NEX-6 and on the A6000).