Do I need to defrost frozen ones oven

I agree with SillyBee! Just pop in your heated oven and slightly increase the baking time. You may want to SLIGHTLY underbake those you are planning to freeze.

I can't say specifically for this recipe but I regularly pop my uncooked, pre-shaped scones directly from the freezer to a pre-heated oven. I know Nancy Birtwhistle (the GBBO winner) does as well. I just bake a tad longer.