Yes, Genesys Cloud SMS supports both inbound and outbound MMS in North America but only a select set of media types are supported in the agent user interface. More specifically agents can send and receive and view .jpg, .png, and .gif media in the agent user interface. Genesys Cloud can receive other media types are but does not display them in the agent user interface. 

If an end user sends unsupported media in a message, then the agent receives an indication that a media attachment was removed. If an end user sends only unsupported media in a message, then Genesys Cloud notifies the agent that the message has no content.

For more information, see MMS overview.