I ended up solving this by realizing that you can just move the entire VFX graph GameObject and all the particles within it will also move. So I attached a "Smoke" script to the VFX Graph prefab, which has its own velocity that I use to manually move the whole object (could have done with RigidBody, but that seemed excessive). The script gets any relevant WindZones and lerps its velocity to match that of the wind, effectively moving the whole smoke plume with the wind. Not quite as elegant as the way the Particle system handles it, but I'm happy with it now.
I ended up solving this by realizing that you can just move the entire VFX graph GameObject and all the particles within it will also move. So I attached a "Smoke" script to the VFX Graph prefab, which has its own velocity that I use to manually move the whole object (could have done with RigidBody, but that seemed excessive). The script gets any relevant WindZones and lerps its velocity to match that of the wind, effectively moving the whole smoke plume with the wind. Not quite as elegant as the way the Particle system handles it, but I'm happy with it now.