I wouldn't call the ADI-2 FS an "analogue preamplifier", then IMHO the device would also need analogue inputs like the Pro model, but the ADI-2 DAC FS has no analogue inputs.
But even an ADI-2 Pro would first digitize an analogue input signal, no matter whether the output is analogue or digital. The reason is the design, all DSP features can only happen in the digital domain, so everything goes through the DSP.
Only the ADI-2 FS, with significantly fewer features, supports the routing from an analogue input to an analogue output inside the analogue domain (without AD/DA conversion).
The question is what your demand is, where your preference is.
I wouldn't be too worried, the AD/DA conversion quality and features of the ADI-2 DAC/FS series are outstanding.
Should you require analogue inputs or other features, then you require an ADI-2 Pro FS.
If you need e.g. to connect a turntable, check the ADI-2/4 Pro SE.
BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub14