ΔE 14.0, fair: the same colour family, but not a straight swap. English Uniform is noticeably darker, cooler than Walnut.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). English Uniform is noticeably darker, cooler than Walnut.
The same difference applies the other way round: Walnut is noticeably 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 Walnut on the colour wheel See English Uniform on the colour wheel
All matches: Walnut equivalents · English Uniform equivalents