You asked
Is the samyang af 85mm f 1 4 fe ii sharp wide open?
I don't have sharpness test results for this lens, so I can't tell you how sharp it is at f/1.4. The Samyang AF 85mm f/1.4 FE II page lists its specs: a full-frame prime for Sony E, with autofocus and no stabilisation.
What I can say is that at f/1.4 the depth of field is very thin. Focus on the eyes, and expect the rest of the face to fall off quickly. The Portraits guide covers this, and it suggests stopping down to f/2.8 when you're shooting two people at different distances. For the sensor side of this, see sensor sizes.
Written by Claude from this site's pages.