How do I add a function to be able to create a new issue another project and auto link them

[Maria Noer]

I want to have a button or selection within one project that would allow me to spawn an new issue (with ability to select issue type and Project) so that I can create it in another Project and have it automatically linked.    We have found a script that will allow us to do that except it won't let us do it across projects only within the project. 

[PucciG]

you might need to install scriptrunner which has built in post functions that supports this: see link to atlassian advise: https://confluence.atlassian.com/jirakb/how-to-create-new-issue-with-different-project-during-post-function-776664100.html