Leafy Green vs Lemon Green

How close are they?

ΔE 25.3, loose: different enough that you should pick on purpose. Lemon Green is noticeably lighter, much more muted than Leafy Green.

Can I use Lemon Green instead of Leafy Green?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 25). Lemon Green is noticeably lighter, much more muted than Leafy Green.

Can I use Leafy Green instead of Lemon Green?

The same difference applies the other way round: Leafy Green is noticeably darker, much 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.