ΔE 27.7, loose: different enough that you should pick on purpose. Light Sea Blue is noticeably lighter, much more saturated, cooler than Lucky 38.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 28). Light Sea Blue is noticeably lighter, much more saturated, cooler than Lucky 38.
The same difference applies the other way round: Lucky 38 is noticeably darker, 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 Lucky 38 on the colour wheel See Light Sea Blue on the colour wheel
All matches: Lucky 38 equivalents · Light Sea Blue equivalents