To make fig balsamic glaze: stem and mince the figs. Pour vinegar into a small saucepan. Stir in figs and sugar. Turn heat onto medium high and cook for 6 minutes, stirring occasionally. Cool for 10 minutes.
Slice watermelon into six 1-inch rounds. Cut each watermelon round into six wedges.
Drizzle fig balsamic glaze over the slices and sprinkle on feta, oregano, and Maldon salt.