Place blueberries in a small saucepan and add 1/2 cup sugar, 1 Tbsp. water and lemon zest. Bring to a boil over high heat, then reduce heat to medium-low and simmer, stirring often, until berries are softened and releasing liquid, about 5 minutes. Force berries through a fine-mesh sieve into a large bowl; discard solids. (You will have about 1/2 cup strained pulp and juice.) Cover and refrigerate until well chilled, about 1 hour.
Preheat oven to 350°F. Spread almonds on a rimmed baking sheet and toast, stirring often, until lightly browned and fragrant, about 5 minutes. Remove from baking sheet and cool.
Combine cream and yogurt in a large bowl. Add remaining 2 Tbsp. sugar and beat with an electric mixer on high speed until mixture forms stiff peaks. Divide whipped cream into 2 parts and gently fold one half into blueberries.
Spoon some plain whipped cream into bottom of 8 4- or 6-oz. glasses. Add a layer of raspberries to each, placing them around edges so they're visible. Top with a layer of blueberry mixture. Continue layering until glasses are full. Refrigerate for at least 1 hour. Top with berries and toasted almonds just before serving.