ΔE 13.7, fair: the same colour family, but not a straight swap. Cobalt Violet Hue is a little darker, warmer than Warlock Purple.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Cobalt Violet Hue is a little darker, warmer than Warlock Purple.
The same difference applies the other way round: Warlock Purple is a little lighter, 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 Warlock Purple on the colour wheel See Cobalt Violet Hue on the colour wheel
All matches: Warlock Purple equivalents · Cobalt Violet Hue equivalents