In a small nonreactive saucepan, combine the blueberries, sugar, wine and water. Scrape the seeds from the vanilla bean pieces into the pan; add the vanilla bean pieces to the pan. Set over medium heat, partially cover and bring to a brisk simmer. Cook, stirring occasionally, until the mixture has reduced and is slightly syrupy, about 7 minutes. Remove from heat. Transfer the syrup to a heat proof bowl and cool to room temperature. Cover and refrigerate until cold, at least 2 hours, or overnight.
Remove the vanilla bean pieces from the syrup. In a food processor, puree the syrup.
In a large bowl, stir together the plums, peaches, syrup and lemon juice. The dessert can be served immediately or it can be refrigerated for up to 1 hour.
Spoon the fruit mixture into dessert bowls, dividing the syrup evenly and using it all. Sprinkle each portion with some of the mint and serve immediately.