ΔE 16.6, loose: different enough that you should pick on purpose. Seraphim Sepia is a little lighter, much more muted than Light Tone.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Seraphim Sepia is a little lighter, much more muted than Light Tone.
The same difference applies the other way round: Light Tone is a little 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 Light Tone on the colour wheel See Seraphim Sepia on the colour wheel
All matches: Light Tone equivalents · Seraphim Sepia equivalents