ΔE 11.5, fair: the same colour family, but not a straight swap. Ahriman Blue is a little darker, cooler than Navy Blue.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Ahriman Blue is a little darker, cooler than Navy Blue.
The same difference applies the other way round: Navy Blue 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 Navy Blue on the colour wheel See Ahriman Blue on the colour wheel
All matches: Navy Blue equivalents · Ahriman Blue equivalents