In a saucepan, heat pomegranate juice and sugar over medium heat until dissolved (3–5 minutes). In a bowl, sprinkle gelatin over cold water to bloom for 5 minutes. Stir melted gelatin into juice mixture and cool before folding in whipped heavy cream.

Preheat oven to 350°F (175°C). Whisk eggs and sugar until pale and thick (5 minutes). Fold in flour, melted butter, and vanilla until combined. Pour into lined baking pan and bake for 20–25 minutes.

Cut sponge into circles. Spoon mousse into molds filling halfway and press sponge on top. Tap molds to release air bubbles and freeze for at least 4 hours.

Combine chocolate, pomegranate juice, corn syrup, and gelatin in a heatproof bowl. Melt together and stir until smooth. Cool to 90–95°F before using.

Remove domes from freezer, unmold onto rack. Pour glaze over domes, coating completely. Freeze for 30 minutes, then transfer to a serving plate.