In «ضَرَبَ زَيْدٌ عَمْرًا», naming the object identifies the person affected. If the listener already knows that Zayd struck someone, «عَمْرًا» may be the main new information.
If the question is instead “Did Zayd strike at all?”, the important claim is the occurrence of striking by Zayd. Naming a particular object may then provide information that was not being requested.
Thus a verb's grammatical transitivity does not alone determine what belongs in the utterance. The point of assertion and the hearer's existing knowledge are decisive.