The current version of Word has new (as opposed to legacy) form fields which are added using the developer toolbar. The legacy form fields can be preserved when exporting to PDF using Aspose.Words by setting the PdfSaveOptions.PreserveFormFields property.
Is there a way to preserve these new form fields?
Unfortunately, there is no way to represent content control (new form fields) in PDF as editable. However, we suggest you please convert the content controls into form fields and save PDF using PdfSaveOptions.PreserveFormFields property. Please read the following articles.
https://docs.aspose.com/words/net/working-with-content-control-sdt/