ΔE 23.6, loose: different enough that you should pick on purpose. Medium Yellow is noticeably lighter, much more saturated, cooler than Yellow Ochre.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 24). Medium Yellow is noticeably lighter, much more saturated, cooler than Yellow Ochre.
The same difference applies the other way round: Yellow Ochre 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 Yellow Ochre on the colour wheel See Medium Yellow on the colour wheel
All matches: Yellow Ochre equivalents · Medium Yellow equivalents