Combine liqueur, 1 tablespoon sugar, water, and espresso powder, stirring until sugar and espresso powder dissolve. Spoon 2 tablespoons mixture into a medium bowl; set remaining mixture aside.
Add remaining 1/4 cup sugar and creamer to 2 tablespoons liqueur mixture in bowl, stirring until sugar dissolves. Add cream cheese; beat at medium speed of an electric mixer until smooth. Fold in whipped topping.
Place 1 cake slice in each of 8 wine glasses or 8 (4-ounce) custard cups. Brush cake in glasses generously with half of reserved liqueur mixture. Spread cheese mixture evenly over cake. Top with remaining 8 cake slices. Gently press slices into glasses. Brush cake with remaining liqueur mixture. Sprinkle evenly with cocoa, if desired. Serve immediately.