ΔE 10.3, fair: the same colour family, but not a straight swap. Abaddon Black is a little darker, more muted than Brown Black.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 10). Abaddon Black is a little darker, more muted than Brown Black.
The same difference applies the other way round: Brown Black 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 Brown Black on the colour wheel See Abaddon Black on the colour wheel
All matches: Brown Black equivalents · Abaddon Black equivalents