The Chains feature currently supports (most) built in effects (these appear above the divider in the Effect menu) and Nyquist plug-ins. Other effect plug-ins (LADSPA and VST) are not currently supported.
You could try installing this (Nyquist) reverb plug-in to see if you can achieve a suitable effect: https://forum.audacityteam.org/t/stereo-reverb/20310/1