Not all replies show in default language

We have found that once you click the Translate button on a conversation that has many back and forth emails, it will translate the customer's message from French to English which is what we want.  However, by default, it will show the agents reply in French.  This means that for every single agent response we have to click “Show Original” to be able to read what they wrote and follow the conversation.  That should not be the default behavior.