Note this caveat:
"Note: Configuration Sync cannot be performed with a combined network. "
A combined network is any network with more than one device type in it.
What you might be able to do is use by backup/restore script, and then when you do a restore delete all the settings except just the WiFi and restore those settings into the other networks.
http://www.ifm.net.nz/cookbooks/meraki-backup.html