ΔE 14.9, fair: the same colour family, but not a straight swap. Black is noticeably darker, more muted than Battlefield Brown.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 15). Black is noticeably darker, more muted than Battlefield Brown.
The same difference applies the other way round: Battlefield Brown is noticeably 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 Battlefield Brown on the colour wheel See Black on the colour wheel
All matches: Battlefield Brown equivalents · Black equivalents