ΔE 10.3, fair: the same colour family, but not a straight swap. Emerald is a little darker than Jade Green.
✓ Herrick Games paint comparison chart lists these two as equivalents.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 10). Emerald is a little darker than Jade Green.
The same difference applies the other way round: Jade Green is a little lighter.
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 Jade Green on the colour wheel See Emerald on the colour wheel
All matches: Jade Green equivalents · Emerald equivalents