ΔE 13.1, fair: the same colour family, but not a straight swap. Celestial Violet is noticeably darker, more saturated than Purple Quasar.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Celestial Violet is noticeably darker, more saturated than Purple Quasar.
The same difference applies the other way round: Purple Quasar is noticeably lighter, 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 Purple Quasar on the colour wheel See Celestial Violet on the colour wheel
All matches: Purple Quasar equivalents · Celestial Violet equivalents