I found this on the internet:
( I do think that Azamara will arrange some sort of transportation both from the airport and from central Venice.)
Venice to Chioggia Cathedral by bus, ferry and walk
The journey time between Venice and Chioggia Cathedral is around 1h 41m and covers a distance of around 17 miles. This includes an average layover time of around 23 min. Operated by ACTV S.p.a, the Venice to Chioggia Cathedral service departs from Santa Maria Elisabetta and arrives in Chioggia Cathedral. Typically 213 services run weekly, although weekend and holiday schedules can vary so check in advance.