ΔE 11.1, fair: the same colour family, but not a straight swap. Fey Pink is a little lighter, warmer than Matt Pink. They are different kinds of paint: AMMO by Mig Matt Pink is an ink, glaze or transparent paint and Army Painter Fey Pink is an opaque base/layer 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). Fey Pink is a little lighter, warmer than Matt Pink. They are different kinds of paint.
The same difference applies the other way round: Matt Pink is a little darker, cooler.
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 Matt Pink on the colour wheel See Fey Pink on the colour wheel
All matches: Matt Pink equivalents · Fey Pink equivalents