You can't instantiate bx console as a mono plugin in Reaper or Samplitude because of the way they interact with plugins.  I believe this is true for any plugin, in fact.  But don't worry; all you have to do is switch the Stereo Mode to "Digital."  This way, it will apply the same TMT hardware modeling to the left and the right, so it will sound exactly the same as a mono instance of the bx console.