ΔE 13.6, fair: the same colour family, but not a straight swap. Lemon Yellow is a little darker, more muted, cooler than Sunny Yellow.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Lemon Yellow is a little darker, more muted, cooler than Sunny Yellow.
The same difference applies the other way round: Sunny Yellow is a little 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 Sunny Yellow on the colour wheel See Lemon Yellow on the colour wheel
All matches: Sunny Yellow equivalents · Lemon Yellow equivalents