Preheat oven to 300 degrees F.
Beat aquafaba in a standing mixer until peaks start forming. Gradually add 2 1/2 cups powdered sugar, then cornstarch, vinegar, and vanilla. Continuing whipping until fluffy with stiff peaks (this takes a bit longer than whipping egg whites).
Place rounds of aquafaba on silpat-lined baking sheets. Bake for 90 minutes or until crisp on the outside, yet tender inside. Cool completely.
While cooling, whip coconut cream, gelatin dissolved in the vanilla, and 2/3 cup powdered sugar. Beat until fluffy, with stiff peaks.
Layer meringues with whipped cream and half of the fruit. Top with second meringue, more cream, and remaining berries. Garnish with edible petals.