ΔE 8.4, close: similar, with a visible difference side by side. Japan. Unif. WWII is a little darker, more muted than Faded Khaki.
Usually, if you are not matching paint already on the model. Close match (ΔE 8). Japan. Unif. WWII is a little darker, more muted than Faded Khaki.
The same difference applies the other way round: Faded Khaki is a little lighter, 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 Faded Khaki on the colour wheel See Japan. Unif. WWII on the colour wheel
All matches: Faded Khaki equivalents · Japan. Unif. WWII equivalents