If you want to make this dairy-free, feel free to sub the half and half for coconut milk, and the 2% milk for soy milk or light coconut milk.
Feel free to add 1/4 tsp rosewater (you can increase to taste) if you want to add a touch of floralness to your drink. The main flavors will still be the earl grey and matcha.
If you’re not concerned about making distinct layers, no need to ensure that the different liquids are at specific temperatures, nor do you need to be careful when pouring the drink into the glass. Dump it all in - you’ll get a creamy green color once you mix and it looks like a normal matcha latte!