The passive voice just switches the roles so that the patient is the subject and the agent is the object (e.g. in "The ball was kicked by John," the ball is still the patient despite being the subject). It's just that with English word order, it also switches the places of the things in the sentence.

In languages with more flexible word order, you could just switch the two without passive voice. You could just say the equivalent of "The ball kicked John," with it being clear somehow that the ball is the grammatical object and John the subject, without needing to use the passive voice at all.