Thank you for using Syncfusion products.
In DocIO, text form field has been preserved with the following structure.
Essential DocIO internally adds FieldSeparator, FieldResult and FieldEnd while adding the TextFormField item to the paragraph. If you need to hide the TextFormField, then you need to set the hidden property as true for all the elements. So that you can able to hide the StyleRef field result also. We have prepared a sample to illustrate the same. Please find the sample from the below link
In the input template document, we have inserted the StyleRef field with Heading1 style in header which refer the PersonName TextFormField with same Style in the body, fill the form field data and set the hidden property as true.
Please let us know in case of any other questions.
Thank you for your update.
Currently DocIO doesn’t provide support for StyleRef field in Word document to Pdf and Image conversions. We have already logged this a feature request in our database. A support incident to track the status of this feature has been created under your account. Please log on to our support website to check for further updates
Please let me know if you have any questions.