It is always an advantage to stay in the digital domain as long as possible because of the lossless nature of digital transport.

The manual of the Behringer says that the EQ works on the digital level and you can choose:

1. whether you want to make the digital connection via AES or ADAT. For Optical would speak here the galvanic separation.

2. if you want to do the D/A conversion on the DEQ2496 or on the RME 802. The manual says that you can choose input and output freely, e.g. analog, AES, SPDIF.

3. you can even choose for the output port which signal should be output there: the unprocessed input signal (MAIN IN or DIG. IN), the processed signal behind the graphic and parametric EQs (BEHIND GEQ/PEQ), the processed signal behind the EQs and the dynamics module (DYN), or the processed signal behind all modules, i.e. behind the stereo imager module (BEHIND WIDTH).

The 802 seems to have the better D/A converters. Behringer has 113dB dynamic range (less), RME has 115dB (more).
It might be the case, that also other values are better on the RME 802 side..

Therefore I would connect the monitors to the 802 and loop the DEQ2496 in via ADAT.

Then all analog signals will be A/D converted on the 802, there it stays digital in its routing matrix.
There you send it lossless through ADAT to the Behringer.
There the signals are also processed digitally.
You get the signal back via ADAT.
And the final D/A conversion then happens finally on the 802 through analog ports to e.g monitors and phones.