ΔE 13.0, fair: the same colour family, but not a straight swap. Flesh Wash is noticeably lighter than Soft Tone.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Flesh Wash is noticeably lighter than Soft Tone.
The same difference applies the other way round: Soft Tone is noticeably darker.
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 Soft Tone on the colour wheel See Flesh Wash on the colour wheel
All matches: Soft Tone equivalents · Flesh Wash equivalents