ΔE 17.5, loose: different enough that you should pick on purpose. Oxide Brown Light is a little darker, much more saturated, cooler than Sylvaneth Bark.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Oxide Brown Light is a little darker, much more saturated, cooler than Sylvaneth Bark.
The same difference applies the other way round: Sylvaneth Bark is a little lighter, much more muted, 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 Sylvaneth Bark on the colour wheel See Oxide Brown Light on the colour wheel
All matches: Sylvaneth Bark equivalents · Oxide Brown Light equivalents