ΔE 22.7, loose: different enough that you should pick on purpose. Stonewall Grey is a little darker, much more muted than Neo Pink.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 23). Stonewall Grey is a little darker, much more muted than Neo Pink.
The same difference applies the other way round: Neo Pink is a little lighter, much more saturated.
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 Neo Pink on the colour wheel See Stonewall Grey on the colour wheel
All matches: Neo Pink equivalents · Stonewall Grey equivalents