ΔE 15.3, loose: different enough that you should pick on purpose. Algae Green is noticeably darker, cooler than Matt Light Olive Drab. They are different kinds of paint: AMMO by Mig Matt Light Olive Drab is an ink, glaze or transparent paint and Army Painter Algae Green is a one-coat contrast-style paint, so they won’t behave the same on the model even where the colour is close.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Algae Green is noticeably darker, cooler than Matt Light Olive Drab. They are different kinds of paint.
The same difference applies the other way round: Matt Light Olive Drab is noticeably lighter, 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 Matt Light Olive Drab on the colour wheel See Algae Green on the colour wheel
All matches: Matt Light Olive Drab equivalents · Algae Green equivalents