How to populate data from different project to a custom field while issue creation

[Sindhu]

I have a project-A which has client name added. when i create issue on project-B the client name field should auto populate, based on what client is added on project-A. 

[Sayed Bares _ServiceRocket_]

@Sindhu If you want to set the client field automatically based on Project A while creating the issue then you'd need an app like Behaviours - ScriptRunner for Jira Cloud 
 (More options).

If you want to set the client field when the issue is created then you can use automation (Issue created (trigger)+ Edit issue (action)).

[Sindhu]

am not sure how to use scriptrunner, do you have any code which i can test ?

[Sayed Bares _ServiceRocket_]

@Sindhu you can refer to this Behaviour  example as a start: https://docs.adaptavist.com/sr4jc/latest/features/behaviours/example-behaviour#change-field-name-example