Initial data values of FRAM devices
If memory is reliably initialized to some value, then that would be a feature a manufacturer would most definitely put in their data sheets.

If it's not in the data sheet, it's not something that a manufacturer will guarantee (and which might either simply never be the case, or subject to change at no notice, e.g. when the memory testing routine changes).

If it's not guaranteed to be in a certain state, you can't rely on it being in a certain state, and would just have to initialize it yourself.

Unless you're in a very power-constrained environment, this isn't a bad thing. You don't have to do that initialization as a production step! Instead:

I assume you're going to attach that memory to some microcontroller. Simply reserve some specific memory area to contain an "unlikely" value – for example, just 4 random bits that you hardcode into your MCU firmware. Your microcontroller reads that area, and if these bytes are there, it knows, the memory is initialized. If it's not, it initializes it – since the datasheet promises "no wait states during writes", and the thing supports SPI at 20 MHz, initializing the whole 2048 B would take about 0.1 ms.