ΔE 13.6, fair: the same colour family, but not a straight swap. Orc Flesh Wash is a little darker, much more saturated, cooler than Necrosis Green Wash.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Orc Flesh Wash is a little darker, much more saturated, cooler than Necrosis Green Wash.
The same difference applies the other way round: Necrosis Green Wash is a little lighter, much 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 Necrosis Green Wash on the colour wheel See Orc Flesh Wash on the colour wheel
All matches: Necrosis Green Wash equivalents · Orc Flesh Wash equivalents