If it's a FPGA, you should be able to reprogram it to perform whatever algorithms you want, provided you have the know-how, or know someone with the know-how that likes money.
The FPGA is one thing, how it is wired on the board is important as well. E.g. HDMI decryption would need high speed I/O in both directions. Up to 10.2 Gbit/s video + 36.86 Mbit/s audio. Which of the mining boards can do that? The application is very different from Bitcoin mining, where you don't need high speed I/O at all. 300 bit/s would be plenty.
WPA2 needs a little more I/O than Bitcoin mining. Enough that I wonder if some boards may hit a bottleneck without adding some extra logic to the FPGA, but what do I know. There are many applications with I/O needs in between. E.g. filtering in a SDR.