Convert unresolved cross references to text when publishing a topic outside of its book

Hi All. Using FM 16.0.4 on Windows with a customised Responsive HTML settings file. I'm re-using topics across multiple books which is causing issues with cross references when publishing each book. If I have a cross reference from one topic A to another topic B, but then use topic A (but not B) in another book then I'd prefer to have the cross reference convert to simple text rather than a broken hyperlink in HTML. Currently thinking of using conditional markers to have alternative links, but wondering if there's a more automated way of converting the cross reference to text when publising to HTML. 

Help, input, discussion, much appreciated 🙂