There is a Nyquist plug-in called “Multi-Voice Chorus” available here: https://forum.audacityteam.org/t/chorus-effect/26335/1
Installing Nyquist plug-ins on a Mac may be found here: https://manual.audacityteam.org/man/installing_effect_generator_and_analyzer_plug_ins_on_mac_os_x.html#nyquist_install
In case you don’t know, there is a mailing list specifically for blind Audacity users. Information about this can be found here: https://wiki.audacityteam.org/wiki/Audacity_for_blind_users#Documentation_and_mailing_lists