ΔE 17.4, loose: different enough that you should pick on purpose. Poison Green is a little darker, more muted, warmer than Gremlin Green.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Poison Green is a little darker, more muted, warmer than Gremlin Green.
The same difference applies the other way round: Gremlin Green is a little lighter, more saturated, 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 Gremlin Green on the colour wheel See Poison Green on the colour wheel
All matches: Gremlin Green equivalents · Poison Green equivalents