Enclosing/Casing Design for electronics (electronic eng. vs industrial designer)
Since the aesthetics of the enclosure are often what distinguish your product in the marketplace, it is an industrial designer, not an industrial engineer, who should be doing the enclosure design.  Your company may have one in-house, or hire one as a consultant.

The industrial designer will be working with any other engineers involved in the project, such as electrical, mechanical, and industrial, plus a human factors person, and will be responsible for seeing that the enclosure meets all the electrical, mechanical, and regulatory requirements of the product.

I don't see that an electrical engineer would be too involved in the initial case design, except to give to the industrial designer a BOM of all the large parts anticipated to be used in the design.  Often, a case design will be influenced by whatever type of display is being used and other user interface features (buttons, etc.).  There may be some back and forth between the EE and the industrial designer on some of these components.

After a case design has been proposed, then the EE would need to make sure there is enough room for whatever PCB's are needed and also cutouts for connectors, that there is adequate height for tall components, and any thermal considerations are taken care of.

The industrial designer will typically render models of the enclosure using a 3D CAD program like SolidWorks.  Programs like this can usually exchange files with PCB layout programs like Altium Designer, for example, to make sure mechanical features of a PCB like a cutout for a mounting post like up exactly.

3D modelling programs can be used to design enclosures that will be produced either in metal or plastic.  Prototypes are usually made using 3D printing.  Later, instructions for making a mold or CNC instructions for making a metal enclosure can be output from the CAD program.

When designing the enclosure, it is important for the industrial designer to keep manufacturing costs in mind; adding additional complexity to a mold can easily cost an extra $10,000.