ΔE 20.8, loose: different enough that you should pick on purpose. Crimson Magenta is noticeably lighter, more saturated, warmer than Orchid Purple.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 21). Crimson Magenta is noticeably lighter, more saturated, warmer than Orchid Purple.
The same difference applies the other way round: Orchid Purple is noticeably darker, more muted, 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 Orchid Purple on the colour wheel See Crimson Magenta on the colour wheel
All matches: Orchid Purple equivalents · Crimson Magenta equivalents