ΔE 15.5, loose: different enough that you should pick on purpose. Reddish Flesh is noticeably lighter, more muted than Sekigahara.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Reddish Flesh is noticeably lighter, more muted than Sekigahara.
The same difference applies the other way round: Sekigahara is noticeably darker, 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 Sekigahara on the colour wheel See Reddish Flesh on the colour wheel
All matches: Sekigahara equivalents · Reddish Flesh equivalents