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A ghost piloting their own zombie in the way you describe would be Possessing a Dead Body overlapping with People Puppets.
The Disembodied is a closely related concept, where the body isn't properly dead, but the soul has been separated from it in some way.
Edited by Scorpion451

A character's disembodied spirit and reanimated body both existing and being active at the same time. They can either be entirely independent or have some kind of connection, such as being subject to Synchronization or the ghost being able to control the zombie like a reverse Fighting Spirit, but the ghost exists outside the zombie. The only example I can think of from an entry that has a page is The Forgotten from The Binding of Isaac, but there's an even better example in this Newgrounds animation
.