ΔE 17.7, loose: different enough that you should pick on purpose. Arrakis Brown is noticeably darker, warmer than Inner Light.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Arrakis Brown is noticeably darker, warmer than Inner Light.
The same difference applies the other way round: Inner Light is noticeably lighter, 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 Inner Light on the colour wheel See Arrakis Brown on the colour wheel
All matches: Inner Light equivalents · Arrakis Brown equivalents