Dryad Bark vs Dark Skin

How close are they?

ΔE 15.2, loose: different enough that you should pick on purpose. Dark Skin is a little lighter, more saturated than Dryad Bark.

Can I use Dark Skin instead of Dryad Bark?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Dark Skin is a little lighter, more saturated than Dryad Bark.

Can I use Dryad Bark instead of Dark Skin?

The same difference applies the other way round: Dryad Bark is a little darker, more muted.

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.