ΔE 15.2, loose: different enough that you should pick on purpose. Straken Green is much more saturated than Dark Olive Green FS-34130.
Can I use Straken Green instead of Dark Olive Green FS-34130?
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Straken Green is much more saturated than Dark Olive Green FS-34130.
Can I use Dark Olive Green FS-34130 instead of Straken Green?
The same difference applies the other way round: Dark Olive Green FS-34130 is much more muted.
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.