ΔE 49.6, loose: different enough that you should pick on purpose. Ink Magenta is a little lighter, more muted, warmer than Inktense Violet.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 50). Ink Magenta is a little lighter, more muted, warmer than Inktense Violet.
The same difference applies the other way round: Inktense Violet is a little darker, more saturated, cooler.
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 Inktense Violet on the colour wheel See Ink Magenta on the colour wheel
All matches: Inktense Violet equivalents · Ink Magenta equivalents