ΔE 15.3, loose: different enough that you should pick on purpose. Celestial Violet is a little darker, more saturated, cooler than Kunzite Alchemy.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Celestial Violet is a little darker, more saturated, cooler than Kunzite Alchemy.
The same difference applies the other way round: Kunzite Alchemy is a little lighter, more muted, 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 Kunzite Alchemy on the colour wheel See Celestial Violet on the colour wheel
All matches: Kunzite Alchemy equivalents · Celestial Violet equivalents