Jordy Vandeput, one of the creators behind Cinecom, is a fantastically enthusiastic, entertaining, and informative instructor. He teaches a course for people starting out with Unreal (or who want to touch up on foundational concepts). The course is focused on using Unreal for Virtual Production, but most of the topics covered apply to game development as well. While the course can be purchased standalone, I recommend signing up for Skillshare as you then get access to tons of other tutorials as well!
This guide from Unreal covers how to:
While not covering Metahumans specifically, this is a great animation pipeline from Prompt Muse that covers several helpful tools, including:
Unreal Sensei is an incredible teacher with a wide range of free and paid content to help others learn Unreal. I started my Unreal journey with Unreal Sensei and highly recommend checking out their channel!
This video from Feeding Wolves provides a good overview of how to bake and tweak facial animation using a Backward Additive Solver.
Maris Freimanis is another fantastic Unreal Engine instructor. He even has a Discord channel for Unreal support that can be joined from the link in the description of this video. Speaking of this video, it is a thorough overview of how to apply Mixamo animation assets to Metahuman bodies. I recommend checking out his guide alongside my Metahuman Body Animation guide, as I made some changes to account for a few issues I ran into when trying to replicate Maris's process.