ΔE 17.7, loose: different enough that you should pick on purpose. Brutal Brown is more muted, cooler than XV-88.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Brutal Brown is more muted, cooler than XV-88.
The same difference applies the other way round: XV-88 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 XV-88 on the colour wheel See Brutal Brown on the colour wheel
All matches: XV-88 equivalents · Brutal Brown equivalents