ΔE 18.2, loose: different enough that you should pick on purpose. Temple Guard Blue is a little darker, much more saturated, cooler than Freezing Moon.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Temple Guard Blue is a little darker, much more saturated, cooler than Freezing Moon.
The same difference applies the other way round: Freezing Moon is a little lighter, 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 Freezing Moon on the colour wheel See Temple Guard Blue on the colour wheel
All matches: Freezing Moon equivalents · Temple Guard Blue equivalents