ΔE 48.7, loose: different enough that you should pick on purpose. Fluorescent Green is noticeably darker, more saturated, cooler than Fluor Yellow.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 49). Fluorescent Green is noticeably darker, more saturated, cooler than Fluor Yellow.
The same difference applies the other way round: Fluor Yellow 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 Fluor Yellow on the colour wheel See Fluorescent Green on the colour wheel
All matches: Fluor Yellow equivalents · Fluorescent Green equivalents