ΔE 10.8, fair: the same colour family, but not a straight swap. Olive Green is a little darker, more muted, warmer than Kasrkin Green.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Olive Green is a little darker, more muted, warmer than Kasrkin Green.
The same difference applies the other way round: Kasrkin Green is a little lighter, more saturated, cooler.
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 Kasrkin Green on the colour wheel See Olive Green on the colour wheel
All matches: Kasrkin Green equivalents · Olive Green equivalents