ΔE 18.6, loose: different enough that you should pick on purpose. Cultist Purple is noticeably lighter, cooler than Purple.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 19). Cultist Purple is noticeably lighter, cooler than Purple.
The same difference applies the other way round: Purple is noticeably darker, 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 Purple on the colour wheel See Cultist Purple on the colour wheel
All matches: Purple equivalents · Cultist Purple equivalents