ΔE 7.6, close: similar, with a visible difference side by side. Dark Olive is more muted than WWI French Green 2.
Usually, if you are not matching paint already on the model. Close match (ΔE 8). Dark Olive is more muted than WWI French Green 2.
The same difference applies the other way round: WWI French Green 2 is 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 WWI French Green 2 on the colour wheel See Dark Olive on the colour wheel
All matches: WWI French Green 2 equivalents · Dark Olive equivalents