Wizards Orb vs Grayish Blue FS35237

How close are they?

ΔE 9.8, close: similar, with a visible difference side by side. Grayish Blue FS35237 is a little darker, more muted than Wizards Orb.

Can I use Grayish Blue FS35237 instead of Wizards Orb?

Usually, if you are not matching paint already on the model. Close match (ΔE 10). Grayish Blue FS35237 is a little darker, more muted than Wizards Orb.

Can I use Wizards Orb instead of Grayish Blue FS35237?

The same difference applies the other way round: Wizards Orb is a little lighter, more saturated.

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.