ΔE 14.9, fair: the same colour family, but not a straight swap. Prussian Blue Hue is a little darker, more muted than Highlord Blue. They are different kinds of paint: Army Painter Highlord Blue is a one-coat contrast-style paint and Golden Prussian Blue Hue is an ink, glaze or transparent 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 15). Prussian Blue Hue is a little darker, more muted than Highlord Blue. They are different kinds of paint.
The same difference applies the other way round: Highlord Blue 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.
See Highlord Blue on the colour wheel See Prussian Blue Hue on the colour wheel
All matches: Highlord Blue equivalents · Prussian Blue Hue equivalents