ΔE 12.5, fair: the same colour family, but not a straight swap. Hiril Blue is more muted, cooler than Royal Cloak.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Hiril Blue is more muted, cooler than Royal Cloak.
The same difference applies the other way round: Royal Cloak is more saturated, warmer.
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 Royal Cloak on the colour wheel See Hiril Blue on the colour wheel
All matches: Royal Cloak equivalents · Hiril Blue equivalents