The /wiki/api/v2/pages/{id} endpoint is used to change the page owner, as detailed in https://jira.atlassian.com/browse/CONFCLOUD-76294 :

• https://developer.atlassian.com/cloud/confluence/rest/v2/api-group-page/#api-pages-id-put  

Currently, this API differs from the Confluence UI by creating a new page version and requiring the content body in the request, even when the content remains unchanged.

We kindly request that new page versions not be created when only the page owner is updated. Additionally, we would appreciate it if the body and version properties could be made optional when the ownerId property is included in the request body.

Thanks.