ΔE 12.7, fair: the same colour family, but not a straight swap. Dark Green is a little lighter, more saturated, cooler than Russian Green 4BO.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Dark Green is a little lighter, more saturated, cooler than Russian Green 4BO.
The same difference applies the other way round: Russian Green 4BO is a little darker, more muted, 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 Russian Green 4BO on the colour wheel See Dark Green on the colour wheel
All matches: Russian Green 4BO equivalents · Dark Green equivalents