ΔE 36.2, loose: different enough that you should pick on purpose. Estus Yellow is noticeably lighter, more saturated, warmer than Gutrippa Flesh.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 36). Estus Yellow is noticeably lighter, more saturated, warmer than Gutrippa Flesh.
The same difference applies the other way round: Gutrippa Flesh is noticeably darker, more muted, cooler.
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 Gutrippa Flesh on the colour wheel See Estus Yellow on the colour wheel
All matches: Gutrippa Flesh equivalents · Estus Yellow equivalents