ΔE 16.6, loose: different enough that you should pick on purpose. Dusky Grape is noticeably darker, cooler than Mulled Berry.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Dusky Grape is noticeably darker, cooler than Mulled Berry.
The same difference applies the other way round: Mulled Berry is noticeably lighter, 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 Mulled Berry on the colour wheel See Dusky Grape on the colour wheel
All matches: Mulled Berry equivalents · Dusky Grape equivalents