Eloquent ORM many-to-many relationship between string and int primary keys

I have been struggling to make this happen, but every time I failed.

Eloquent ORM many-to-many relationship between string and int primary keys

I have been struggling to make this happen, but every time I failed.

Eloquent ORM many-to-many relationship between string and int primary keys

I have been struggling to make this happen, but every time I failed.

Laravel true polymorphic “many-to-many” relation

Laravel doc provides polymorphic “many-to-many” sample (pivot table taggables) with the following structure: