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