I'm not sure there is a solution to your problem, but there are things you can try.

You could try projecting on the entire document, then manually getting values from the projected document. For Lucene, use ProjectionConstants.DOCUMENT which will return a org.apache.lucene.Document. For Elasticsearch, use ElasticsearchProjectionConstants.SOURCE which will return the full document source as a String. Obviously, performance will degrade, but it might be acceptable for your use case.

If you really need to, you could bypass the query DSL completely and execute queries yourself. Be warned: it can get pretty complicated, especially for Lucene. For Lucene, use the index reader accessor. For Elasticsearch, use the REST client directly