ΔE 8.0, close: similar, with a visible difference side by side. Pearl Grey is a little darker than Fairy Dust. They are different kinds of paint: Army Painter Fairy Dust is a metallic and Scale75 Pearl Grey is a pearl paint, so they won’t behave the same on the model even where the colour is close.
Usually, if you are not matching paint already on the model. Close match (ΔE 8). Pearl Grey is a little darker than Fairy Dust. They are different kinds of paint.
The same difference applies the other way round: Fairy Dust is a little lighter.
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 Fairy Dust on the colour wheel See Pearl Grey on the colour wheel
All matches: Fairy Dust equivalents · Pearl Grey equivalents