ΔE 14.2, fair: the same colour family, but not a straight swap. Bronze is noticeably lighter than Iron Warriors.
Can I use Bronze instead of Iron Warriors?
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Bronze is noticeably lighter than Iron Warriors.
Can I use Iron Warriors instead of Bronze?
The same difference applies the other way round: Iron Warriors is noticeably 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.