ΔE 28.9, loose: different enough that you should pick on purpose. Ink Blue is noticeably darker, cooler than Matt Purple.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 29). Ink Blue is noticeably darker, cooler than Matt Purple.
The same difference applies the other way round: Matt Purple is noticeably lighter, 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 Matt Purple on the colour wheel See Ink Blue on the colour wheel
All matches: Matt Purple equivalents · Ink Blue equivalents