You asked
Is the 7artisans 35mm f 1 4 iii hard to focus manually?
The site doesn't say how hard this lens is to focus by hand. What I can tell you is that the 7Artisans 35mm f/1.4 III is manual focus only, with no autofocus, so you'll be doing all the focusing yourself. You can check the 7Artisans 35mm f/1.4 III page for the full list of mounts and the cameras it fits.
Manual focus is easier at f/1.4 than you might expect if you use your camera's focus peaking or magnification, though those features depend on the body. The wide aperture gives very shallow depth of field, so the focus has to land exactly on the eyes or the nearest edge of the subject. For people, the portraits guide explains why a 35mm works well for environmental shots that show where someone is.
Written by Claude from this site's pages.