Greenskin vs Niblet Green

How close are they?

ΔE 15.9, loose: different enough that you should pick on purpose. Niblet Green is noticeably lighter, more saturated, warmer than Greenskin.

Can I use Niblet Green instead of Greenskin?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Niblet Green is noticeably lighter, more saturated, warmer than Greenskin.

Can I use Greenskin instead of Niblet Green?

The same difference applies the other way round: Greenskin is noticeably darker, more muted, 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.