Description

Since version 5.8.0 we have the provision to set the 3rd party to apps custom field while creating multiple issues based on a multi-select third-party custom field. 

Assumption:

Let us assume we have an insight multi-select field and an insight single select field in our system.

Instructions

1. Choose to add the Create issue or Create subtask post function as usual.
2. Configure various options as usual.
3. Find the Create multiple issues parameter.
4. Add a multi/single select 3rd party custom field name. 
   Note : This will create as many new issue/subtasks as many values are there in the parent/original custom field specified.
   
5. Find the Set custom field parameter.

6. Set a third party custom field with the %entry% substitution variable as follows. Provide the original/parent issue custom field name as well in the third input box.
   
   

   You will need to provide the original/parent issue third-party custom field name/id when setting a custom field based on %entry% substitution variable.