ΔE 17.1, loose: different enough that you should pick on purpose. Lemon Green is a little lighter, warmer than Ferocious Green.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Lemon Green is a little lighter, warmer than Ferocious Green.
The same difference applies the other way round: Ferocious Green 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 Ferocious Green on the colour wheel See Lemon Green on the colour wheel
All matches: Ferocious Green equivalents · Lemon Green equivalents