ΔE 12.3, fair: the same colour family, but not a straight swap. Agrax Earthshade is a little lighter, more muted, cooler than Strong Tone.
✓ Army Painter Fanatic conversion chart lists these two as equivalents.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Agrax Earthshade is a little lighter, more muted, cooler than Strong Tone.
The same difference applies the other way round: Strong Tone is a little darker, more saturated, warmer.
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 Strong Tone on the colour wheel See Agrax Earthshade on the colour wheel
All matches: Strong Tone equivalents · Agrax Earthshade equivalents