ΔE 9.4, close: similar, with a visible difference side by side. Steel Blue is a little lighter, warmer than Light Prussian Blue.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Steel Blue is a little lighter, warmer than Light Prussian Blue.
The same difference applies the other way round: Light Prussian Blue is a little darker, 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 Light Prussian Blue on the colour wheel See Steel Blue on the colour wheel
All matches: Light Prussian Blue equivalents · Steel Blue equivalents