ΔE 10.5, fair: the same colour family, but not a straight swap. Rust is a little lighter than Skavenblight Dinge. They are different kinds of paint: Citadel Skavenblight Dinge is an opaque base/layer paint and Vallejo Rust is a fluorescent or effect 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 11). Rust is a little lighter than Skavenblight Dinge. They are different kinds of paint.
The same difference applies the other way round: Skavenblight Dinge is a little darker.
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 Skavenblight Dinge on the colour wheel See Rust on the colour wheel
All matches: Skavenblight Dinge equivalents · Rust equivalents