ΔE 15.1, loose: different enough that you should pick on purpose. Chestnut Brown is noticeably lighter, cooler than Vineroot Shade. They are different kinds of paint: Army Painter Vineroot Shade is a wash/shade and Nocturna Models Chestnut Brown is an opaque base/layer paint, so they won’t behave the same on the model even where the colour is close.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Chestnut Brown is noticeably lighter, cooler than Vineroot Shade. They are different kinds of paint.
The same difference applies the other way round: Vineroot Shade is noticeably darker, 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 Vineroot Shade on the colour wheel See Chestnut Brown on the colour wheel
All matches: Vineroot Shade equivalents · Chestnut Brown equivalents