Line the sides and bottom of an ungreased 9-in. springform pan with ladyfingers, rounded sides out; trim to fit, if necessary. (Save remaining ladyfingers for another use.)
Quickly spread ice cream into prepared pan; freeze, covered, 30 minutes. Spread sorbet over ice cream; freeze 30 minutes longer.
Meanwhile, place strawberries and confectioners' sugar in a food processor; process until pureed. Reserve 1/4 cup puree for swirling. Transfer remaining puree to a large bowl; whisk in marshmallow creme.
In a small bowl, beat cream until soft peaks form. Fold into marshmallow mixture. Spread evenly over sorbet; drizzle with reserved puree. Cut through puree with a knife to swirl. Freeze, covered, overnight.
Remove from freezer; carefully loosen sides from pan with a knife. Remove rim from pan. Serve immediately.