Final answer:
In theme development, the required attributes for all input settings are 'name' and 'type', used for identification and defining input nature respectively.
Step-by-step explanation:
The attributes that are required for all input settings in a theme that presents to merchants are name and type. When creating or editing a theme, these attributes are used to ensure that each input control is properly recognized by the system and displays the correct form element. The name attribute is used as a unique identifier to collect the input's value upon form submission. The type attribute defines the nature of the input, such as 'text', 'checkbox', 'radio', etc., and dictates what kind of data the user can enter into that input field.