I have this question because I have used the RME Multiface II + HDSPe PCI card and it supports TotalMix (not FX at that time). I didn't open up the external box but apart from the card's FPGA, I suppose the external box also has another chip for the interconnect like this (which is an older version but similar product):
I also own this soundcard:
https://hardforum.com/threads/breat...-soundcard-creative-x-fi-titanium-hd.2003840/
The converters:
PCM4220, PCM1794A, WM8775
...as well as the main chip (CA20k2) and a RAM chip. This card can do unlimited multiclient ASIO with multiple effects running concurrently including the more complex one like reverb, as well as simpler ones like parametric and graphic EQ, with assignable aux send and inserts. It is a 10 years old product though I bought the card in 2013. Latency wise of course not as good as the RME products but the chip (perhaps driver?) on the Creative card can do these stuff. So far I don't know what this chip really is so let's say it is a custom ASIC, so I don't know how to compare it with these Xilinx chips, but should be quite feasible for a product released in 2020 I suppose?