I have spent time printing from 80 year old negatives and to get the look you probably need to shoot with a blue filter for landscapes. Most of the amatuer cameras such as Brownies required estimating the depth of field so you find many pictures with plane of focus a little off the mark.

If you are looking at original prints and want to duplicate that look, remember that the negatives were new and the prints now show the effects of aging.
One way to duplicate this would be to get a piece of glass like you might use for contact printing but thin (2-3mm) and smudge, get dirty etc, a little and that might give the print an aged look. Never tried that but seems like it might work. Thin glass is required to reduce distortion printing through the glass.

While working with the old negatives that were pyro developed (circa 1915-1920) when the focus was accurate they were very sharp with very delicate and beautiful highlights. New prints from the old negatives made some people believe the images were of people dressed in period costumes. The only thing that indicated the real date was the "distinct look" of the individuals who looked much older then their true ages.