ΔE 24.0, loose: different enough that you should pick on purpose. Flesh Wash is noticeably lighter, much more muted than Reikland Fleshshade.
✓ Two Thin Coats comparison chart lists these two as equivalents.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 24). Flesh Wash is noticeably lighter, much more muted than Reikland Fleshshade.
The same difference applies the other way round: Reikland Fleshshade is noticeably darker, much more saturated.
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 Reikland Fleshshade on the colour wheel See Flesh Wash on the colour wheel
All matches: Reikland Fleshshade equivalents · Flesh Wash equivalents