Normally, visibility of fields in JIRA is configured with Field Configurations and Screens. The field needs to be configured for the issue type and for the screen to become visible.
I have different issue types in my project and they have different field configurations, each selecting a subset of applicable fields. The screen configurations (e.g. create issue screen) are not issue type dependent and include all fields.
This works well with pretty much all fields, so only those applicable to the issue type are shown.
However, 'Epic Link' can apparently not be configured this way and I am puzzled about the restriction. I want to use Epic Link for some issue types, but not for all. How can I hide it without duplicating all my screens?