ΔE 15.3, loose: different enough that you should pick on purpose. Olive Green is a little darker, much more saturated than Dawnstone.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Olive Green is a little darker, much more saturated than Dawnstone.
The same difference applies the other way round: Dawnstone is a little lighter, much 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.
See Dawnstone on the colour wheel See Olive Green on the colour wheel
All matches: Dawnstone equivalents · Olive Green equivalents