ΔE 5.2, very close: most people won’t see a difference side by side. Bugman's Glow is a little lighter than Earth. They are different kinds of paint: AMMO by Mig Earth is an ink, glaze or transparent paint and Citadel Bugman's Glow is an opaque base/layer paint, so they won’t behave the same on the model even where the colour is close.
Yes, for most jobs. Very close match (ΔE 5). Bugman's Glow is a little lighter than Earth. They are different kinds of paint.
The same difference applies the other way round: Earth is a little darker.
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 Earth on the colour wheel See Bugman's Glow on the colour wheel
All matches: Earth equivalents · Bugman's Glow equivalents