I use it on the Sony Alpha 6000 with a manual FD 50mm. AF and aperture transmission are not an issue here. Actually, the adapter only keeps the lens at the right distance in front of the sensor. This works great and I think it will be the same with the Alpha 7III. 

Could you please update us your full Minolta lens model ?as Minolta has MD MC and AF mount, K&F Concept MD-M4/3 is suitable for: Lens: Minolta MD MC Mount lens(not for Minolta AF mount: KF06.157) Camera: Micro 4/3 (MFT) mount mirrorless camera like Olympus PEN, OM-D series, Panasonic Lumix DMC-G1, G2, G3, G10, GX1, GH1, GH2, GF1, GF2, GF3, GF5, GH4, Panasonic AG-AF100 Mirrorless Digital Cameras, Black Magic Pocket Cinema Camera (BMPCC) 

it could work with a nikon f-mount (d3300) to sony e-mount( a7iii). 

It’s a little tight on my a7III. I bought the Fotodiox brand for my Nikon glass and prefer the fit a bit more. Still works however, just ended up buying a Fotodiox for my Minoltas as well. 

You can shoot in Manual or Aperture Priority Mode. Before use, set your camera Menu: "Shoot without lens".