See, in most professional output things you usually have a trained model (like they now added to unreal or attempted to) which properly adjusts the mesh deform on its own based on bone rotations.
So there is a cost, but not as cumbersome as manually managing JCM (joint control morph)…
Pixar has been doing it for years. Others attempt to add dual quaternions to achieve similar effect (but fail miserably anyway?).
Aside from that, be weary what you learn off a meta human. They do literally nothing properly or best practice…
Its much better to resolve to the older human character documentation… they were way over the top already in terms of quality and features…