Prepare the peaches by washing thoroughly, removing pits, and slicing them into ½-inch wedges. No need to peel them—the skin adds beautiful color and extra flavor.
Bring 2 cups of water to a gentle simmer in a medium saucepan (not boiling—about 175°F/80°C is ideal for green tea to prevent bitterness).
Remove the water from heat and add the green tea bags. Let steep for exactly 3-4 minutes—any longer and the tea may become bitter.
Remove the tea bags and add the sliced peaches to the hot tea. Using a wooden spoon, gently press the peaches to release their juices.
Add honey or maple syrup while the mixture is still warm, stirring until completely dissolved.
Allow the peach-tea mixture to cool for about 15 minutes at room temperature, then transfer to the refrigerator for 1-2 hours to fully infuse the flavors.
Strain the mixture through a fine-mesh strainer into a pitcher, pressing gently on the peaches to extract maximum flavor.
Add the remaining 4 cups of cold water and lemon juice to the pitcher, stirring to combine.
Taste and adjust sweetness if needed by adding more honey or maple syrup.
Serve over ice in tall glasses, garnished with fresh peach slices and mint leaves if desired.