ΔE 10.4, fair: the same colour family, but not a straight swap. Crystal Blue is a little darker, more saturated, warmer than Blue.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 10). Crystal Blue is a little darker, more saturated, warmer than Blue.
The same difference applies the other way round: Blue is a little lighter, more muted, cooler.
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 Blue on the colour wheel See Crystal Blue on the colour wheel
All matches: Blue equivalents · Crystal Blue equivalents