ΔE 22.1, loose: different enough that you should pick on purpose. Temple Guard Blue is noticeably darker, more muted, cooler than Green Blue.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 22). Temple Guard Blue is noticeably darker, more muted, cooler than Green Blue.
The same difference applies the other way round: Green Blue is noticeably lighter, more saturated, 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 Green Blue on the colour wheel See Temple Guard Blue on the colour wheel
All matches: Green Blue equivalents · Temple Guard Blue equivalents