ΔE 14.7, fair: the same colour family, but not a straight swap. Karak Stone is a little lighter, much more muted than Khaki.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 15). Karak Stone is a little lighter, much more muted than Khaki.
The same difference applies the other way round: Khaki is a little darker, much more saturated.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Khaki on the colour wheel See Karak Stone on the colour wheel
All matches: Khaki equivalents · Karak Stone equivalents