There are no buses in Meganisi. All transportation has to be done on foot or by private means. The only 4-star hotel on the island offers few bus trips to the beaches of the island with its small coach, but there is no other public bus to serve visitors.
Moreover, there are no car and motorbike rentals on the island. If you want to get around with car or bike, then you will have to rent it from Lefkada and board it with you on the ferry.