Passengers disembarking the Melbourne-Devonport 'Spirit of Tasmania' ferry in Devonport need to ride the 5 km via the A1 bridge from the terminal on the east side of the Mersey to the town on the west side.  cycle.travel (both website and iPhone app) suggests going by the Mersey Ferry, which ceased operation in 2022 (https://cycle.travel/map/journey/964956).  

The Ferry was discontinued because of lack of patronage - no doubt in part because terrible planning required foot passengers to walk 1.5 km from the Spirit of Tasmania to the small East Devonport Ferry jetty.  The Spirit port is being upgraded, due to finish later in 2027, but I can't imagine they will have thought about making it easier for foot and cycling passengers. Planning does not seem to be their strong suit, given that they are primarily upgrading the port because the new ferries they bought don't fit in the existing port (and are sitting doing nothing at Melbourne while they upgrade).