You can offset the position of a Source (parent) object in a Multi-referential constraint.
To create offsets in a Multi-referential constraint:
- Expand the constraints folder in the Scene browser and double-click the Multi-Referential constraint to select it.
- In the Properties window, expand (Parent object) Offset translation and (Parent object) Offset rotation.
- Set the Offset translation and rotation for the Parent object you want to affect.
- Do this for all the parent objects you want to adjust.
You can key and animate this offset by activating the Key and Animate buttons next to each setting you modify.