While I think that all different depictions and abilities that come with both the Leprechaun and the Easter Bunny could leave the course of this fight to be pretty ambiguous, the Easter Bunny will have the upper hand throughout the duel. He can throw his eggs and baskets at the leprechaun. He can also kick pretty hard, which would be even more advantageous assuming the Bunny is bigger than the Leprechaun. Of course, the Bunny can hop high, which could be helpful if the leprechaun throws gold at him or tries some other sort of ranged attack. The Bunny could also use the baskets for defense in ranged attacks with the gold, by either using it as a shield or redirecting the gold that comes his way back in the Leprechaun’s direction. I feel like the Bunny could also use those big chocolate bunnies that are usually given on Easter. They might break easily, but the Easter Bunny could put some use into them. This doesn’t have any impact on the fight, but I like to imagine that the children supporting the Easter Bunny restock his eggs and baskets during the duel, and the kids helping the Leprechaun restock his gold. I think it would be a fun addition. 

Everyone’s interpretations of the Easter Bunny and the Leprechaun are different, so a hypothetical fight would be hard to put together from the vast number of versions there are of these two festive characters. But based on their most common characteristics, the Easter Bunny is definitely going to win this fight.