ΔE 11.1, fair: the same colour family, but not a straight swap. Aegis Aqua is more saturated, cooler than Deep Sky Blue.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Aegis Aqua is more saturated, cooler than Deep Sky Blue.
The same difference applies the other way round: Deep Sky Blue is more muted, 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 Deep Sky Blue on the colour wheel See Aegis Aqua on the colour wheel
All matches: Deep Sky Blue equivalents · Aegis Aqua equivalents