ΔE 11.5, fair: the same colour family, but not a straight swap. Elfic Blue is noticeably lighter, cooler than Deep Cobalt Blue.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Elfic Blue is noticeably lighter, cooler than Deep Cobalt Blue.
The same difference applies the other way round: Deep Cobalt Blue is noticeably darker, 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 Deep Cobalt Blue on the colour wheel See Elfic Blue on the colour wheel
All matches: Deep Cobalt Blue equivalents · Elfic Blue equivalents