ΔE 6.9, close: similar, with a visible difference side by side. Chestnut Brown is a little lighter, cooler than Dryad Brown.
Usually, if you are not matching paint already on the model. Close match (ΔE 7). Chestnut Brown is a little lighter, cooler than Dryad Brown.
The same difference applies the other way round: Dryad Brown is a little darker, warmer.
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.
See Dryad Brown on the colour wheel See Chestnut Brown on the colour wheel
All matches: Dryad Brown equivalents · Chestnut Brown equivalents