ΔE 25.6, loose: different enough that you should pick on purpose. Temple Guard Blue is noticeably darker, much more saturated than Grey Goose.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 26). Temple Guard Blue is noticeably darker, much more saturated than Grey Goose.
The same difference applies the other way round: Grey Goose is noticeably lighter, 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 Grey Goose on the colour wheel See Temple Guard Blue on the colour wheel
All matches: Grey Goose equivalents · Temple Guard Blue equivalents