Goblin Flesh vs Lime Green

How close are they?

ΔE 15.3, loose: different enough that you should pick on purpose. Lime Green is noticeably darker, more muted than Goblin Flesh.

Can I use Lime Green instead of Goblin Flesh?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Lime Green is noticeably darker, more muted than Goblin Flesh.

Can I use Goblin Flesh instead of Lime Green?

The same difference applies the other way round: Goblin Flesh is noticeably lighter, more saturated.

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.