ΔE 12.5, fair: the same colour family, but not a straight swap. Scarlet is noticeably lighter than Quinacridone Violet.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Scarlet is noticeably lighter than Quinacridone Violet.
The same difference applies the other way round: Quinacridone Violet is noticeably darker.
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 Quinacridone Violet on the colour wheel See Scarlet on the colour wheel
All matches: Quinacridone Violet equivalents · Scarlet equivalents