ΔE 19.1, loose: different enough that you should pick on purpose. Blue Flux is a little lighter, much more saturated, warmer than Ice Blue.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 19). Blue Flux is a little lighter, much more saturated, warmer than Ice Blue.
The same difference applies the other way round: Ice Blue is a little darker, 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 Ice Blue on the colour wheel See Blue Flux on the colour wheel
All matches: Ice Blue equivalents · Blue Flux equivalents