ΔE 13.3, fair: the same colour family, but not a straight swap. Light Turquoise is a little darker, much more saturated, warmer than Ashen Blue.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Light Turquoise is a little darker, much more saturated, warmer than Ashen Blue.
The same difference applies the other way round: Ashen Blue is a little lighter, much 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 Ashen Blue on the colour wheel See Light Turquoise on the colour wheel
All matches: Ashen Blue equivalents · Light Turquoise equivalents