ΔE 19.9, loose: different enough that you should pick on purpose. Ink Black Green is a little lighter, warmer than Turquoise Ink.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 20). Ink Black Green is a little lighter, warmer than Turquoise Ink.
The same difference applies the other way round: Turquoise Ink is a little darker, cooler.
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 Turquoise Ink on the colour wheel See Ink Black Green on the colour wheel
All matches: Turquoise Ink equivalents · Ink Black Green equivalents