ΔE 18.5, loose: different enough that you should pick on purpose. Blue Steel is noticeably lighter, much more saturated than Steel.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Blue Steel is noticeably lighter, much more saturated than Steel.
The same difference applies the other way round: Steel is noticeably darker, much more muted.
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 Steel on the colour wheel See Blue Steel on the colour wheel
All matches: Steel equivalents · Blue Steel equivalents