Most should allow you to do that but one in particular is BigTalker. The only problem is that it isn’t always simultaneous but it will send to multiple speakers that are properly set up to speak in SmartThings.
Announcing BigTalker 2.0 release
Important Notice 1.x users: BigTalker 2.x is not a direct upgrade from 1.x. Configured events from 1.x will not transfer over due to the move from a single app model to a parent/child model.
Have you ever wanted a talking house? Now you can! With the
Big Talker SmartApp (2.x branch)
When SmartThings is paired with a compatible audio device (such as a Sonos, Ubi, LANnouncer, VLCThing, AskAlexa, etc) and Big Talker SmartApp, your house can say what you want it to say when events occur.
Supported events at 2.0.0 release (see documentation link for latest):
Time: Time of Day + Day(s) of Week
Mode: Change (Home, Away, etc)