[aidenn0]

Different editions of Stratego have different wordings for scouts. Some rules are silent on moving and attacking in the same turn (implying that scouts can't move & attack in the same turn), some rules specifically state that the scout cannot move and attack in the same turn. Some rules say they can move and attack in a straight line, and some use the wording you quote.

The ISF rule is that the attack must be in-line with the move[1].

1: https://isfstratego.kleier.net/docs/rulreg/isfgamerules.pdf Section 5.3