I can't really say from the picture. The banana that is visible is large enough to be "just a banana." But if it started out as a water leaf sucker that is the approximate shape the leaves would have been. The sword leaf suckers keep very narrow pointed leaves until they are 2-3' out of the ground. All depends on the exact species, current conditions, situation it was coming out of. The difference is really negligible to the home grower. The sword leaf is a more vigorous grow, so it might yield bananas sooner. But both plants will do just fine and grow to their proper size for you. The concern over destroying water leaf suckers is in the plantations where yields are affected and the weak plants represent the next crop. To those guys every single penny counts.