how could metahuman be incorporated as a character creator within the game?
We cant teach you how to make an entire character creator from scratch. It is possible but it is a large project. Maybe try a character creator from the UE Marketplace and then go from there.
I made a really basic MetaHuman character creator for my game/app Cine Tracer.
They give you all of the components you need to get started and then I started to make my own clothing that “fits” with the stock clothes to maintain the modularity. Their hair a bit tricky to make run time changeable and your AnimBPs and Control Rigs need to be setup properly.