ΔE 10.0, close: similar, with a visible difference side by side. Ion Blue is a little darker, more saturated than Skyshard.
Usually, if you are not matching paint already on the model. Close match (ΔE 10). Ion Blue is a little darker, more saturated than Skyshard.
The same difference applies the other way round: Skyshard is a little lighter, 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 Skyshard on the colour wheel See Ion Blue on the colour wheel
All matches: Skyshard equivalents · Ion Blue equivalents