ΔE 41.1, loose: different enough that you should pick on purpose. Romeo/Juliet is noticeably lighter, much more saturated, cooler than Brazen Copper.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 41). Romeo/Juliet is noticeably lighter, much more saturated, cooler than Brazen Copper.
The same difference applies the other way round: Brazen Copper is noticeably darker, much more muted, 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 Brazen Copper on the colour wheel See Romeo/Juliet on the colour wheel
All matches: Brazen Copper equivalents · Romeo/Juliet equivalents