In a small saucepan, add cold water and sprinkle gelatin over it. Heat gelatin mixture over low heat, until fully dissolved. Remove from heat, and set aside.
In a large saucepan over medium heat, combine oat milk, coconut milk and sugar. Bring to a boil, stirring to help sugar dissolve. Once mixture has heated through and sugar has dissolved, remove from heat
Stir in cinnamon, vanilla extract and gelatin mixture.
Divide mixture into ramekins. Let cool to room temperature; then put in refrigerator to chill, covered, for 4 hours or overnight.
For topping, combine the water, sugar, quick oats and cornstarch in a saucepan; bring to a boil over medium heat. Add peaches, and simmer 2 minutes.
Remove pan from heat, and stir in maple syrup and basil. Spoon over the panna cotta, and serve.
Notes
If you don't want to serve these in the ramekins, dip one at a time into a bowl of hot water for 3 seconds. Run a thin knife around inside edge and invert onto center of a small plate. Tap gently to “pop” panna cotta out.