You can display oriented boxes as model nodes or as annotation ROI nodes.
You can orient them by applying a transform to the node. In case of models, you may create them already oriented (e.g., create the box using vtkCubeSource and rotate using vtkTransformPolyDataFilter) and then you don’t need to use a transform node.
To edit, you can enable Transform/Display/Interaction/Visible in 3D view. This allows translation, rotation, and resizing in 3D. To allow editing in slice views as well, you need to use ROI node (and you may keep the transform interactor for rotation only).