ΔE 20.0, loose: different enough that you should pick on purpose. Deep Blue is noticeably darker, more saturated, cooler than Luxion Purple.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 20). Deep Blue is noticeably darker, more saturated, cooler than Luxion Purple.
The same difference applies the other way round: Luxion Purple is noticeably lighter, 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 Luxion Purple on the colour wheel See Deep Blue on the colour wheel
All matches: Luxion Purple equivalents · Deep Blue equivalents