The Nikkor lenses seem very popular for copy work and you don’t need 1:1 so that opens you up to many macro lens options. Found this in another forum but thought it was useful…
The “6x7” negative size is actually 56 x 67mm.
The Fuji “APS-C” sensor size is 23.6 x 15.6 mm.
So to capture the full “6x7” frame (without cropping it to 3:2 ratio), you need a magnification ratio = 1:(67/15.6) = 1:4.3
If you instead wish to capture a 3:2 aspect ratio crop of the original negative, you need a magnification ratio = 1:(56/23.6) = 1:2.4
In either case, a 1:2 “macro” lens such as Fuji’s XF60/2.4 provides MORE THAN ENOUGH magnification.