ΔE 10.9, fair: the same colour family, but not a straight swap. Black Red is a little darker, cooler than Red Brown 2.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Black Red is a little darker, cooler than Red Brown 2.
The same difference applies the other way round: Red Brown 2 is a little lighter, warmer.
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 Red Brown 2 on the colour wheel See Black Red on the colour wheel
All matches: Red Brown 2 equivalents · Black Red equivalents