The behavior of the Selection box created when dragging from right to left is different to that of the box created when dragging left to right
When selecting elements in a view by dragging a Selection box around the elements (using Element Selection tool), only elements fully inside the box are selected. However, when selecting from right to left, elements that are only partially inside the box, or that overlap with selection box are also selected. Can this behaviour be switched off?
This behavior is a feature of the Element Selection tool and is working as expected. However, if the <Shift> key is tapped while dragging in either direction, the selection mode is inverted from the current inside / overlap direction.
Element Selection - Online Help Documentation