It looks like this might be "The Nether" featuring Jennifer Haley. From a review:
In Jennifer Haley’s drama “The Nether,” the time is the future, and someone is being interrogated about possible crimes committed in a shared virtual reality experience involving a Victorian theme, grown men and prepubescent girls (who don’t actually exist).
The play has turned out to be Haley’s biggest hit yet. Though it premiered in Los Angeles nearly three years ago, the unsettling thriller has caught on. After well-reviewed productions in London and New York, it receives half a dozen domestic productions this year, including at the San Francisco Playhouse, as well as several in Germany and Spain.
Promo video from one production
Found with search terms of "stage play" "virtual reality" virtual atrocities