ΔE 11.4, fair: the same colour family, but not a straight swap. Emerald Green is a little darker, cooler than Lupercal Green.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Emerald Green is a little darker, cooler than Lupercal Green.
The same difference applies the other way round: Lupercal Green 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 Lupercal Green on the colour wheel See Emerald Green on the colour wheel
All matches: Lupercal Green equivalents · Emerald Green equivalents