That’s a great question! Though I’m usually not on the hiring side so this is pure conjecture, because the term is broad I believe it should be accurate to use Motion capture Artist in this case if you are able to handle all that entails, though you will eventually branch out into other software by necessity as most mocap done in Unreal is still mostly brought in from third party programs.
Keywords will mostly focus on your skillset, I’d go with Mocap Actor if all you do is VO and acting without rigging/cleanup skills, but if you’re capable in those arenas Mocap Artist is great.
I do hope we get a more hiring sided individual to chime in here, for their take. As a developer my work is usually rather divorced from the technical art side.