ΔE 17.5, loose: different enough that you should pick on purpose. Alpha Blue is a little lighter, more saturated, cooler than Bright Violet.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Alpha Blue is a little lighter, more saturated, cooler than Bright Violet.
The same difference applies the other way round: Bright Violet is a little darker, 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 Bright Violet on the colour wheel See Alpha Blue on the colour wheel
All matches: Bright Violet equivalents · Alpha Blue equivalents