ΔE 15.0, loose: different enough that you should pick on purpose. Hull Red is more muted, cooler than Mournfang Brown.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Hull Red is more muted, cooler than Mournfang Brown.
The same difference applies the other way round: Mournfang Brown is more saturated, 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 Mournfang Brown on the colour wheel See Hull Red on the colour wheel
All matches: Mournfang Brown equivalents · Hull Red equivalents