Remove Macro relations from the Relations pane the same way you would remove any other Relations constraint.

To delete a Macro relation permanently, right-click it in the Scene browser and select Delete from the contextual menu.

If the Macro is being used in a relation, a warning dialog box appears with the message “The relation constraint x is being used by other Relations. Delete all references to this Macro?”, where x is the name of the relation.

Select Yes to remove the Macro from all Relations constraints.

If the removal of the Macro creates gaps in a constraint, a conversion relation is automatically created to connect the unconnected Relations constraint.