ΔE 15.7, loose: different enough that you should pick on purpose. Sylvaneth Bark is more muted, warmer than RAL 7009 Hellgrau.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Sylvaneth Bark is more muted, warmer than RAL 7009 Hellgrau.
The same difference applies the other way round: RAL 7009 Hellgrau is more saturated, 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 RAL 7009 Hellgrau on the colour wheel See Sylvaneth Bark on the colour wheel
All matches: RAL 7009 Hellgrau equivalents · Sylvaneth Bark equivalents