The course was published this week…
Metahuman Workflows with Faceware Studio
Even though the first half of the course focuses specifically on using Faceware Studio, the modules in the second half are focused on standard functionality in Unreal Engine, and can be used for any animation source. There’s a Module called Animation Sequences, that demos the use of the FFT filtering functionality.
Here’s a link to the course on the Unreal Online Learning portal: