The drag and drop feature of 4D v11 SQL does not allow you to drag a menu bar from one database to another. This can be circumvented by creating a new project form and assigning it the desired menu bar. Then you can drag and drop the new project form from one database to another, and in the process, the assigned menu bar is copied as well.
Menus and menu items are included in the copy, but if a menu item calls a method not in the new database, that method is not copied. The methods must be copied over separately.
As usual take care when copying objects with the same name. You may end up with multiple menus of the same name but different menu items.