ΔE 17.8, loose: different enough that you should pick on purpose. Blue Steel is a little lighter, more muted, cooler than Azure Magic.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Blue Steel is a little lighter, more muted, cooler than Azure Magic.
The same difference applies the other way round: Azure Magic 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 Azure Magic on the colour wheel See Blue Steel on the colour wheel
All matches: Azure Magic equivalents · Blue Steel equivalents