Currently it's not possible to treat the S-Play an Art-Net node to receive Art-Net and output it directly from the DMX ports.
Customers looking to merge the data from another DMX controller with the S-Play's, or have the S-Play take over control of the installation automatically when my main lighting console is unplugged, should do this externally from the S-Play using a separate DMX node using either merging or sACN priority or physical DMX merging hardware.
Achieving this using sACN priority is the simplest method. Simply set the S-Play to transmit sACN on a low universe priority then use an ENTTEC DIN Ethergate 2 port DMX node to convert the sACN data sent by the S-Play over the network to DMX. When another lighting console or control source sends sACN data at a higher priority over the network using the same universe, it will take control of the DMX output
For further information on different merging methods and sACN priority please see our support article.