ΔE 10.8, fair: the same colour family, but not a straight swap. Dryad Bark is a little darker, more muted than WWI French Green 1.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Dryad Bark is a little darker, more muted than WWI French Green 1.
The same difference applies the other way round: WWI French Green 1 is a little lighter, 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.
See WWI French Green 1 on the colour wheel See Dryad Bark on the colour wheel
All matches: WWI French Green 1 equivalents · Dryad Bark equivalents