ΔE 20.5, loose: different enough that you should pick on purpose. Park Green Flat is a little lighter, more saturated, warmer than Coal Black.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 21). Park Green Flat is a little lighter, more saturated, warmer than Coal Black.
The same difference applies the other way round: Coal Black is a little 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 Coal Black on the colour wheel See Park Green Flat on the colour wheel
All matches: Coal Black equivalents · Park Green Flat equivalents