ΔE 14.4, fair: the same colour family, but not a straight swap. Transparent Brown Iron Oxide is more saturated, warmer than Fresh Rust.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Transparent Brown Iron Oxide is more saturated, warmer than Fresh Rust.
The same difference applies the other way round: Fresh Rust is more muted, 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 Fresh Rust on the colour wheel See Transparent Brown Iron Oxide on the colour wheel
All matches: Fresh Rust equivalents · Transparent Brown Iron Oxide equivalents