ΔE 13.3, fair: the same colour family, but not a straight swap. Brown Beast Ink is noticeably darker than Rhinox Hide. They are different kinds of paint: Citadel Rhinox Hide is an opaque base/layer paint and Nocturna Models Brown Beast Ink is an ink, glaze or transparent paint, so they won’t behave the same on the model even where the colour is close.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Brown Beast Ink is noticeably darker than Rhinox Hide. They are different kinds of paint.
The same difference applies the other way round: Rhinox Hide is noticeably lighter.
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 Rhinox Hide on the colour wheel See Brown Beast Ink on the colour wheel
All matches: Rhinox Hide equivalents · Brown Beast Ink equivalents