Sure, Reaper can do that.
It's a bit like trying to make a cake dough in a 30 ton cement mixer, though.
You'd need an interface with at least 6 inputs and 6 outputs. Add spdif in and out if you want to play back Dolby AC encoded DVD's.
If you just want to eq, why not use a system wide eq system. Are you on Windows, Linux or macOS?