Sound Wave Addon connects audio to animation inside Blender. With a single button you can make a character talk: record your voice, for example on your phone, add the file to the addon, and the character opens its mouth synchronously with the recording. Beyond lip sync, the add-on can drive different objects from sound and produce audio visualizations.
Updates have expanded control over keys. You can select any key and assign an audio file to it, add an audio file to keys where they already exist (which replaces them), and add an audio file from anywhere on the timeline. The developer walks through the principle of operation so you can apply it to your own objects.
The add-on covers Blender 2.93 through 5.1 and supports both Cycles and Eevee. It includes documentation and a tutorial video, and is released under the GPL license.