Originally Posted by Penguin

There is no problem. Regardless of if language is written from left to right or right to left text alignment in bubble delegate is left for messages you sent and right for messages received.

May be that should be left-left for left-to-right languages and right-right for right-to-left languages. Need to check how it would look like.

Edit:

Copy /usr/share/harbour-mitakuuluu/qml/BubbleDelegate.qml to ~/.whatsapp/delegates/BubbleDelegate.qml and apply following patch.

Code:

--- /usr/share/harbour-mitakuuluu/qml/BubbleDelegate.qml    2014-04-04 10:50:21.000000000 +0300
+++ BubbleDelegate.qml    2014-04-04 14:55:37.504880480 +0300
@@ -43,7 +43,6 @@
             timeStatusRow.anchors.left = item.left;
             timeStatusRow.anchors.leftMargin = Theme.paddingLarge;
             msginfo.horizontalAlignment = Text.AlignLeft;
-            msg.horizontalAlignment = Text.AlignLeft;
             playerPlaceholder.anchors.right = item.right
             playerPlaceholder.anchors.leftMargin = Theme.paddingSmall
             setTickView();
@@ -70,7 +69,6 @@
                 msginfo.horizontalAlignment = Text.AlignRight;
                 msg.anchors.right = item.right;
                 msg.anchors.rightMargin = Theme.paddingLarge;
-                msg.horizontalAlignment = Text.AlignRight;
                 timeStatusRow.anchors.right = item.right;
                 timeStatusRow.anchors.rightMargin = Theme.paddingLarge;
             }

Then select BubbleDelegate.qml from settings and there you have it. It does not mirrow the whole UI, it only makes text align naturally either to left or right depending on writing in use.