Hello there,
I've been working on many characters for more than 8 years and I use marvelous designer for clothes, so you will get really high quality simulated-based clothes. I add final touches in zbrush later on and I use Substance painter and Photoshop for realistic texturing.
I assume you provide the model for your character or a mock up so I can make the clothes for her, If not I can use one of my own models as a dummy. But I believe you only need the clothes, right ?
One thing confused me though, you mentioned baked light !!! If its going to be used in game engine, its not necessary to bake shadows and such or maybe I misunderstood your words.
Anyways I can deliver a model with ALL the textures you need for PBR or none-PBR game engines. I've been working with UE4 for a long time so you will get best result for game.
Kind regards