ΔE 16.6, loose: different enough that you should pick on purpose. Violet is a little darker, warmer than Dark Drab.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Violet is a little darker, warmer than Dark Drab.
The same difference applies the other way round: Dark Drab is a little lighter, 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.
See Dark Drab on the colour wheel See Violet on the colour wheel
All matches: Dark Drab equivalents · Violet equivalents