In a small saucepan, bring milk to a simmer over medium heat. Remove the hot milk from the heat and stir in the loose-leaf Marco Polo tea. Let the tea steep in the milk, stirring occasionally, for about 5-7 minutes. Strain into a large bowl and set aside, discarding the used tea leaves.
While the tea is steeping, soak the gelatin sheets in cold water for about 5-7 minutes.
In a medium saucepan, heat the cream and 6 tablespoons of the sugar over medium heat until the sugar is dissolved. Remove from heat and add to reserved tea-steeped milk mixture along with a small pinch of salt.
Remove the soaked gelatin sheets from the water and squeeze out any excess liquid. Add the gelatin sheets to the hot cream/milk mixture, and stir until the gelatin is dissolved. Strain the mixture into a 4-cup measuring cup. Divide the liquid tea panna cotta between six small ramekins, teacups or glasses. Cover with plastic wrap and refrigerate until set, 3 hours to overnight.
About 10-15 minutes before serving, toss the diced strawberries with the remaining 2 tablespoons of sugar and let macerate. To serve, spoon the macerated berries over the chilled panna cotta.