hmm good point, I hadn’t considered that it could be implemented like this. I had assumed that if the link was already a UUID it would be used but you’re probably right that it’s going to be regenerated.
EDIT: Actually I think it could work, see api-random-page-names/src/main/java/org/xwiki/contrib/validation/uuidpages/UUIDEntityNameValidation.java at master · xwiki-contrib/api-random-page-names · GitHub (the page naming strategy has 2 apis: transform & validate). So validate() should work if you provide a UUID-matching pattern.