XV-88 vs Dubai Brown

How close are they?

ΔE 16.4, loose: different enough that you should pick on purpose. Dubai Brown is noticeably darker, more muted than XV-88.

Can I use Dubai Brown instead of XV-88?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Dubai Brown is noticeably darker, more muted than XV-88.

Can I use XV-88 instead of Dubai Brown?

The same difference applies the other way round: XV-88 is noticeably lighter, more saturated.

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.