ΔE 53.5, loose: different enough that you should pick on purpose. Ink Black Green is noticeably darker, much more muted, cooler than Permanent Green Light.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 53). Ink Black Green is noticeably darker, much more muted, cooler than Permanent Green Light.
The same difference applies the other way round: Permanent Green Light is noticeably 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 Permanent Green Light on the colour wheel See Ink Black Green on the colour wheel
All matches: Permanent Green Light equivalents · Ink Black Green equivalents