ΔE 8.6, close: similar, with a visible difference side by side. Ancient Forest is a little lighter, more muted, warmer than Steel Legion Drab.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Ancient Forest is a little lighter, more muted, warmer than Steel Legion Drab.
The same difference applies the other way round: Steel Legion Drab is a little darker, more saturated, 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 Steel Legion Drab on the colour wheel See Ancient Forest on the colour wheel
All matches: Steel Legion Drab equivalents · Ancient Forest equivalents