You may use the "Name Value List" or "Name Lookup Value List" field type. Probably this will serve your purpose of Name+Value for dropdown. To check more out-of-box field types, please see [enter link description here][1]. If out-of-box field types will not be used in your scenario you may add your own field types following this link [enter link description here][2]


  [1]: https://sitecore.namics.com/2018/12/20/cheatsheetfieldtypes/
  [2]: https://doc.sitecore.com/developers/90/web-forms-for-marketers/en/create-a-custom-field-type.html