ΔE 15.5, loose: different enough that you should pick on purpose. Coven Purple is a little lighter, much more saturated than Bright Violet.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Coven Purple is a little lighter, much more saturated than Bright Violet.
The same difference applies the other way round: Bright Violet is a little darker, much more muted.
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 Bright Violet on the colour wheel See Coven Purple on the colour wheel
All matches: Bright Violet equivalents · Coven Purple equivalents