Will an SSR work with mains voltage less than 240V? Which datasheet parameter mentions this?
The link is a "product selector" table. It lists input voltage ranges, that are actually control signal voltage ranges. It also lists output voltage ranges and current values that are the ranges for switched voltages and maximum switched currents.

Pick a relay that has an "output" voltage range that contains the secondary voltage of your transformer and a current that is equal to or preferably, a little greater than your  load current requirement.

The selected SSR also needs to have an input voltage range that contains the control signal that you want to use.

Then look at the individual spec sheet detail to make sure there is nothing else that you need to be concerned about.