Thanks for your question and welcome to the Prodigy community
Have you watched @SofieVL's Relations Extraction video and tutorial:
You may also find this post to be helpful:
This post helps explains why there isn't a simple approach as spaCy doesn't have a built-in relation prediction component:
You may also find using spaCy's GitHub Discussions forum to be more helpful as training relations is more of a spaCy problem than a Prodigy. The spaCy core team supports that forum and they can help answer. There are already related posts like:
