ΔE 11.2, fair: the same colour family, but not a straight swap. Magenta is a little lighter, warmer than Witchbane Plum.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Magenta is a little lighter, warmer than Witchbane Plum.
The same difference applies the other way round: Witchbane Plum is a little darker, 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 Witchbane Plum on the colour wheel See Magenta on the colour wheel
All matches: Witchbane Plum equivalents · Magenta equivalents