ΔE 56.4, loose: different enough that you should pick on purpose. Fluorescent Blue is noticeably lighter, much more muted, cooler than Psychedelic Purple.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 56). Fluorescent Blue is noticeably lighter, much more muted, cooler than Psychedelic Purple.
The same difference applies the other way round: Psychedelic Purple is noticeably darker, much more saturated, 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 Psychedelic Purple on the colour wheel See Fluorescent Blue on the colour wheel
All matches: Psychedelic Purple equivalents · Fluorescent Blue equivalents