This issue has been closed as 'Won't Fix' due to an extended period of time without updates. If this issue is important to you please let us know by posting on the AnswerHub or UDN, and Epic will re-open the ticket for further review.
When mousing over the Enable Metal / High - end mobile rendering preview box, return summary is Enables Environment Queries editor.
Head over to the existing Questions & Answers thread and let us know what's up.