ΔE 12.6, fair: the same colour family, but not a straight swap. Azure is a little lighter, more muted, cooler than Purple.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Azure is a little lighter, more muted, cooler than Purple.
The same difference applies the other way round: Purple is a little darker, more saturated, 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 Purple on the colour wheel See Azure on the colour wheel
All matches: Purple equivalents · Azure equivalents