ΔE 19.4, loose: different enough that you should pick on purpose. Light Blue RLM76 is noticeably darker, much more muted, warmer than Cobalt Bluegreen.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 19). Light Blue RLM76 is noticeably darker, much more muted, warmer than Cobalt Bluegreen.
The same difference applies the other way round: Cobalt Bluegreen is noticeably lighter, much more saturated, cooler.
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 Cobalt Bluegreen on the colour wheel See Light Blue RLM76 on the colour wheel
All matches: Cobalt Bluegreen equivalents · Light Blue RLM76 equivalents