ΔE 15.8, loose: different enough that you should pick on purpose. Light Blue (Luftwaffe) is a little darker, much more muted than Aquamarine.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Light Blue (Luftwaffe) is a little darker, much more muted than Aquamarine.
The same difference applies the other way round: Aquamarine is a little lighter, much more saturated.
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 Aquamarine on the colour wheel See Light Blue (Luftwaffe) on the colour wheel
All matches: Aquamarine equivalents · Light Blue (Luftwaffe) equivalents