ΔE 16.9, loose: different enough that you should pick on purpose. Moon Mist Grey is noticeably darker, more saturated than Matt White.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Moon Mist Grey is noticeably darker, more saturated than Matt White.
The same difference applies the other way round: Matt White is noticeably lighter, more muted.
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 Matt White on the colour wheel See Moon Mist Grey on the colour wheel
All matches: Matt White equivalents · Moon Mist Grey equivalents