ΔE 25.6, loose: different enough that you should pick on purpose. Electric Blue is a little lighter, much more saturated, cooler than Grey Blue.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 26). Electric Blue is a little lighter, much more saturated, cooler than Grey Blue.
The same difference applies the other way round: Grey Blue is a little darker, much 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 Grey Blue on the colour wheel See Electric Blue on the colour wheel
All matches: Grey Blue equivalents · Electric Blue equivalents