Choose field to reference in relationship field?

[adesombergh]

I was wondering if there is any way to reference another collection using the relationship field, but instead of referencing the id (which is default) i need to reference another indexed field, such as externalId.
The reason why i need to do this is because I sync data from an external API that has a different id that the one created by payload.

The ideal scenario would be:

{
  type: 'relationship',
  name: 'related',
  relationTo: 'other_collection',
  reference: 'externalId'
}