Thanks @brock for the advice.  Right now I use FS2 for Active/Bypass and FS5 for Learn, but I’d like to assign Learn to Aux Switch 1 for less toe tapping.

If I follow your instructions it seems like the assignments are made to the builtin foot switches but can be also triggered externally.  If I also assign FS5 to be triggered by Aux Switch 1 then it does trigger Learn but also triggers Active/Bypass as well as tap tempo!  That seems odd.  What would be nice would be to assign Learn to an external controller without a dependency on the built in foot switches.