Route multiple analog (audio) signals using a single switch
Don't give up on mechanical switches yet.



Figure 1. A selection of stackable switches (and some non-stackable).

Stackable switches generally have "decks" made of twelve outer contacts with 1, 2, 3, 4 or 6 wipers enabling switch configurations from 2-way to 12-way with any number of poles subject to the mechanical limitations of the frame.

The regular sized ones I'm familiar with (top right) may be too large for the guitar body but the PCB type pictured may work for you. There may also be a miniature version of the one on the top right.