ΔE 8.8, close: similar, with a visible difference side by side. IJN Gray Green Nakajima is a little darker, cooler than Autumn Sage.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). IJN Gray Green Nakajima is a little darker, cooler than Autumn Sage.
The same difference applies the other way round: Autumn Sage is a little lighter, warmer.
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 Autumn Sage on the colour wheel See IJN Gray Green Nakajima on the colour wheel
All matches: Autumn Sage equivalents · IJN Gray Green Nakajima equivalents