I think  it is possible to change the date format of an input widget with type "date" in a survey form to dd/MM/yyyy. To do this, you can use the "format" property of the input widget.

Here's an example of how you can set the format property:

{    "type": "input",    "name": "myDate",    "inputType": "date",    "title": "Select a date",    "format": "dd/MM/yyyy" } 

In the above example, the "format" property is set to "dd/MM/yyyy", which specifies the date format as day/month/year. You can adjust this format string to suit your needs.

Note that the "format" property is specific to the survey library you're using, so the syntax may differ depending on the library. The example above uses the default format property syntax for the SurveyJS library.

I hope this helps!