Uefy 2.0 (Pro Edition) make Blender's rigify rigs compatible with UE5, also has a FREE version

Thanks for your review! Glad the script is working out for you.

Currently the script is geared towards getting custom characters rigged and exported to Unreal Engine with new animations made with Rigify. Modifying existing animations might sound very similar but really it is quite a different task. I do have some ideas on how to get that going but my priority for my own project was to get new characters into the engine and have them talking.