Software switch for VLAN to bridge with FortiAP

Currently, I use a physical port to create a virtual switch between my SSID & LAN network.  This allows me to keep the wifi clients in the same VLAN/network range as another physical network.  Is it possible to create this software switch on the VLAN level so I don't have to waste a port for each different network I might want to co-exist with IPs of a physical network?