On a Sharepoint online list, you can acitvate the ability to have entreprise keyword column. (list setting/Enterprise Metadata and Keywords Settings /Entreprise Keyword)
when creating an item with the metadata field "entreprise keyword, in Sharepoint you can enter some new keyword which are not in the existing "entreprise keyword" metadata list.
when you turn the form in Nintex form, you can only select existing terms in the entreprise keyword metadata, you cannot add new term anymore
Thank you very much for posting your feedback for our review. At this time, we will not be adding this request to the near-term backlog, as we are focused on other highly requested features. However, we reevaluate requests every quarter and will reach out if priorities change. Please keep the feedback coming as it is critical for our longer-term planning.