ΔE 17.5, loose: different enough that you should pick on purpose. Ink Black Green is a little darker, much more muted, cooler than Sap Green Hue.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Ink Black Green is a little darker, much more muted, cooler than Sap Green Hue.
The same difference applies the other way round: Sap Green Hue is a little lighter, much more saturated, 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 Sap Green Hue on the colour wheel See Ink Black Green on the colour wheel
All matches: Sap Green Hue equivalents · Ink Black Green equivalents