>>3312727well are you shooting portraits at night in front of neon signs? are you shooting paid models in a studio with two rim lights and a bunch of alienbees? are you shooting in broad daylight?
your settings always depend on your environment. there is no magic bullet setting that will work everywhere.
are you on manual? I'll assume you're shooting full manual, and in RAW.
here's some general tips for portrait photography.
1: always aim to keep your ISO low. with a Sony mirroless it's not as big a deal, but generally speaking, higher ISO means more noise, less color accuracy, and a crunchier looking image. shoot with as low an ISO as you can. in broad daylight, this should be 100 - 400. in the shade it should be 400 - 800. at dawn or dusk it should be 800 - 1600.
2: pick your aperture based on your lens, the distance from your subject to the background, and your desired depth of field.
2a: a slow aperture (high f number - f/5.6, f/8, f/11) will give you more sharpness across the image and a progressively deeper field of focus. it will let less light in, so you have to compensate accordingly.
2b: a fast aperture (low f number - f/2.8, f/2, f/1.4) will give you less sharpness overall but should still be sharp in the center with a good lens. it will give you a shallower depth of field and that creamy, soft portrait look, and it will let more light in.
3: pick your shutter speed. if your subject is in front of a highway and you want to get blurry car lights, have them hold very still and shoot at 1/80. if your subject is twitchy and your hand is shaking shoot them at 1/250.
it's all relative. tl;dr - shoot with ISO as low as possible, play with aperture to get more or less of a portrait look.
the biggest variable is your lens, not your body. a 50mm prime is going to give you way different portraits than a 24-70mm telephoto.
