python – flask-admin creates the form and disables some fields in the edit form

A flask manager form is created with all fields enabled and editable.
However, I would like to render the edit mode so that the user can only edit one of the form fields.

Using this unfortunately disables all but one field (as expected for editing) but also in the create form.

form_widget_args = {
    "control": {"readonly": True, "disabled": True},
    "from_dt": {"readonly": True, "disabled": True}, 
    "column": {"readonly": True, "disabled": True}, 
    "values": {"readonly": True, "disabled": True}

How to enable all fields in create mode while disabling a subset of those in edit mode?