ΔE 13.8, fair: the same colour family, but not a straight swap. Light Emerald is noticeably lighter, more saturated than Arphen Jade.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Light Emerald is noticeably lighter, more saturated than Arphen Jade.
The same difference applies the other way round: Arphen Jade 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 Arphen Jade on the colour wheel See Light Emerald on the colour wheel
All matches: Arphen Jade equivalents · Light Emerald equivalents