Sony’s unique hot shoe arrangement is accommodated by an adapter enabling full functionality for your FJ-X2m trigger and compatible Sony camera (https://www.fjwestcott.com/fj-x2m-sony-adapter). You can use the trigger on a Sony camera without the adapter but no HSS or TTL functioning is available in that configuration.
For High-Speed Synchronization, HSS needs to be entered on the FJ-X2m or your Sony camera will limit the maximum sync speed setting to its normal sync between 1/160 and 1/250. Standard in-camera menu settings like silent shooting "off" and E-front curtain "off" apply. Red Eye reduction must be set to "Off". For standard operation, Sony cameras require you to set the Flash mode in-camera menu to "fill-flash". Wireless Flash must be turned to "OFF" or the trigger will default all operations to TTL. Rear curtain sync must be set in-camera on many Sony models.