Is it a job of mechanical specialty to design wine bottles?

This is called "bottle design", and the appearance should be done by professional industrial designers. You need to convert other people's sketches (or sludge models) into three-dimensional models for later mold opening. This has little to do with machinery, and the software used is mechanical, such as Pro/E, UG, CATIA, solidworks and so on. Mainly to make curved surfaces, which require smoothness. There are many similar jobs, such as car body, home appliance shell, toy shell and so on. These are all made by people with mechanical background. Of course, just making bottles should be monotonous. Once the software is used, it can be transferred to structural design. This requires knowledge accumulation in mold, sheet metal and plastics, but the software is a beginner.