ΔE 15.5, loose: different enough that you should pick on purpose. Druchii Violet is a little lighter, more muted, warmer than Purple Tone.
✓ Army Painter Fanatic conversion chart lists these two as equivalents.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Druchii Violet is a little lighter, more muted, warmer than Purple Tone.
The same difference applies the other way round: Purple Tone is a little darker, more saturated, cooler.
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 Purple Tone on the colour wheel See Druchii Violet on the colour wheel
All matches: Purple Tone equivalents · Druchii Violet equivalents