Green Pearl vs Dusken Green

How close are they?

ΔE 26.7, loose: different enough that you should pick on purpose. Dusken Green is a little lighter, much more saturated, warmer than Green Pearl.

Can I use Dusken Green instead of Green Pearl?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 27). Dusken Green is a little lighter, much more saturated, warmer than Green Pearl.

Can I use Green Pearl instead of Dusken Green?

The same difference applies the other way round: Green Pearl is a little darker, much 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.