Can we use formula fields in lookup filters or how do I implement lookup filter to match `D.A` to be equal to `C.B.A`?

Question

I am trying to introduce a lookup filter.

I have standard object A, standard object D which has lookup to A and custom object B__c which has lookup to A and custom object C__c which has lookup to B__c and custom object E__c which has both lookups to C__c and D.

Is this possible to introduce a lookup filter on object E__c relation to D to require D__r.A to be equal to C__r.B__r.A__c ?

I have tried to create a Formula(Text) field on both E__c and C__c to have value of C__r.B__r.A__c but looks like I can't use that field to match field value from D__r.A and also it doesn't allow me to select more than one relationship depth.

Am I missing something? Is there a better way or simply put, any administrative point-and-click way to require D__r.A to be equal to C__r.B__r.A__c ?

This has to be implemented in Group Edition, so I can't use Apex Triggers or advanced configuration options like process builders. Also I don't want to implement a manage package only for that to be installed in the subscriber organization.

Answer 1

Due to documentation,

Lookup filter criteria can’t reference these types of fields on the source object:

Blockquote

Autonumber

Encrypted

Formula

Long text area

Multi-select picklist

Roll-up summary

Text

Text area

URL

and to this documentation link, it is possible to choose related fields that are one relationship away from the lookup object.

Select a suggested field from the Field text box. You can only select fields on the current record, the lookup object, or the user record. You can also choose related fields that are one relationship away from the lookup object. Salesforce assists you by listing the available fields and relationships when you click the lookup icon or click inside the text box.

Answer 2

Since you will not be able to use lookup filter, you can apply this logic in a validation rule and block the users