ΔE 26.2, loose: different enough that you should pick on purpose. Elfic Blue is a little lighter, much more saturated than Freezing Moon.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 26). Elfic Blue is a little lighter, much more saturated than Freezing Moon.
The same difference applies the other way round: Freezing Moon is a little darker, much 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 Freezing Moon on the colour wheel See Elfic Blue on the colour wheel
All matches: Freezing Moon equivalents · Elfic Blue equivalents