ΔE 11.1, fair: the same colour family, but not a straight swap. Iridescent Pink/Gold is a little darker, more saturated than Fairy Dust. They are different kinds of paint: Army Painter Fairy Dust is a metallic and Tamiya Iridescent Pink/Gold is a pearl paint, so they won’t behave the same on the model even where the colour is close.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Iridescent Pink/Gold is a little darker, more saturated than Fairy Dust. They are different kinds of paint.
The same difference applies the other way round: Fairy Dust 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 Fairy Dust on the colour wheel See Iridescent Pink/Gold on the colour wheel
All matches: Fairy Dust equivalents · Iridescent Pink/Gold equivalents