ΔE 10.4, fair: the same colour family, but not a straight swap. Leather Brown is noticeably darker than Space Yellow.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 10). Leather Brown is noticeably darker than Space Yellow.
The same difference applies the other way round: Space Yellow is noticeably lighter.
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 Space Yellow on the colour wheel See Leather Brown on the colour wheel
All matches: Space Yellow equivalents · Leather Brown equivalents