This is already available as per comments and also the related idea here - https://community.rws.com/ideas/trados-portfolio-ideas/i/trados-studio/add-hyperlink-tags-to-target-which-don-t-exist-in-source. However, indeed adding new hyperlinks that don't exist in the source is not possible. It would also be interesting to know in which cases this may be needed - i.e. where a source document does not have a hyperlink and you need to add a new one?