ΔE 11.9, fair: the same colour family, but not a straight swap. Park Green Flat is noticeably lighter, more saturated than Lupercal Green.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Park Green Flat is noticeably lighter, more saturated than Lupercal Green.
The same difference applies the other way round: Lupercal Green is noticeably darker, more muted.
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 Park Green Flat on the colour wheel
All matches: Lupercal Green equivalents · Park Green Flat equivalents