This was reported by an insider WABetaInfo. According to him, WhatsApp is testing self-destructing messages in group chats. However, they must appear in personal correspondence.
This works so far as follows: in the settings of the messenger, or rather a specific chat, you can activate the option "Disappearing messages." For them, it is proposed to choose the time of removal: five seconds or one time.
This means that sending only one self-destructing message will NOT work. The option will apply to everything in the chat.
So far, the function is only at the initial development stage. When it becomes available to all users is unknown.