In a large saucepan over medium-high heat, combine wine, port, sugar, cinnamon stick, vanilla seeds and pod, and salt. Bring to a boil, stirring until sugar dissolves. Reduce heat to medium-low and add dried plums. Keep mixture at a gentle boil until liquid is syrupy, about 45 minutes. Let cool at least 15 minutes. Discard cinnamon stick and vanilla pod. Roughly chop or slice 18 plums.

Place mascarpone and lemon zest in a medium bowl; stir to combine. To serve, put a crepe on a plate; spread 2 tablespoons mascarpone along lower edge. Top with chopped plums. Fold crepe sides inward, partly over filling, and then roll up from the bottom; place seam side down. Repeat with remaining ingredients. Serve, drizzled with syrup and decorated with extra plums, if desired.