ΔE 12.7, fair: the same colour family, but not a straight swap. Imperial Fist is a little darker, warmer than Deep Yellow. They are different kinds of paint: AK Interactive Deep Yellow is an opaque base/layer paint and Citadel Imperial Fist is a one-coat contrast-style paint, so they won’t behave the same on the model even where the colour is close.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Imperial Fist is a little darker, warmer than Deep Yellow. They are different kinds of paint.
The same difference applies the other way round: Deep Yellow is a little lighter, 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 Deep Yellow on the colour wheel See Imperial Fist on the colour wheel
All matches: Deep Yellow equivalents · Imperial Fist equivalents