Flex-table-card

1 row = 1 entity.
Each column may contain:

  • a state (sensor.my_sensor.state);
  • an attribute’s value (sensor.my_sensor.my_attribute);
  • a processed state’s value (Foo(sensor.my_sensor.state));
  • a processed attribute’s value (Foo(sensor.my_sensor.my_attribute)),

but not these:

  • a combination of a state & attributes (sensor.my_sensor.state + sensor.my_sensor.my_attribute + sensor.my_sensor.my_attribute_2);
  • data from another sensors.

Means - you need to PREPARE data before displaying them in flex-table-card - probably define a template sensor with attributes storing all your data.

Update: check this also.