To show the ACF Relationship widget inside the ACF Repeater, we will use ACF Repeater Widget & ACF Relationship Widget.
This tutorial requires Advanced Custom Fields Pro.
In the continuance of our Nested Repeaters Tutorial, we have added writer custom post type and used it in the relationship field inside the Main Repeater.
Now in my ACF Repeater Template 1, I am showing:
Lessons Repeater Field
Writer Relationship using ACF Relationship widget (with below settings)
We can also use a template in Render mode.