ΔE 18.2, loose: different enough that you should pick on purpose. Phthalo Green is much more muted, cooler than Kabalite Green.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Phthalo Green is much more muted, cooler than Kabalite Green.
The same difference applies the other way round: Kabalite Green is 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 Kabalite Green on the colour wheel See Phthalo Green on the colour wheel
All matches: Kabalite Green equivalents · Phthalo Green equivalents