WordNet sense 1 (a workplace that serves as a telecommunications facility where lines from telephones can be connected together to permit communication):

central, telephone exchange

WordNet sense 2 (give to, and receive from, one another):

change, interchange

WordNet sense 3 ((sports) an unbroken sequence of several successive strokes):

rally

WordNet sense 4 (the act of putting one thing or person in the place of another:):

commutation, substitution

WordNet sense 5 (exchange a penalty for a less severe one):

commute, convert, convert

WordNet sense 6 (change over, change around, as to a new order or sequence):

switch, switch over