Importing characters with facial rigging and extras

Hello, I have a doubt about the import of characters with facial rigging, I have read that it is better to separate the head from the body and then bring them together in Unreal for better manage the of animations.
Is there any tutorial about this somewhere?
Does the head rigging also need a root bone at the origin of the character, or is it added to an existing one of the body?
Is it also useful to add extra mesh to the characters, such as tails or wings and in the body continue using the mannequin animations (like a human with wings)?

Thanks for the help.

Overall they need the same skeleton even if separated in parts. So you need to create a “fit all” rig anyway.