A relationship with properties does not point towards both entities anymore but is a directed relationship. We do not make any assumptions if the TargetNode is an end or a start node. This is defined in the relationship-defining class.
Assuming the RelationshipValue is used in Decision and this should get connected to Characteristic, you would define something like:
@RelationshipProperties
public class RelationshipValue {
@Id
@GeneratedValue
private Long graphId;
@TargetNode
private Characteristic characteristic;
and in Decision
public class Decision {
@Relationship("HAS_VALUE_ON") // direction can be OUTGOING (default) or INCOMING
private RelationshipValue relationshipValue;
}