ΔE 12.9, fair: the same colour family, but not a straight swap. Molten Bronze is noticeably lighter, more saturated than True Copper.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Molten Bronze is noticeably lighter, more saturated than True Copper.
The same difference applies the other way round: True Copper is noticeably darker, more muted.
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 True Copper on the colour wheel See Molten Bronze on the colour wheel
All matches: True Copper equivalents · Molten Bronze equivalents