Project templating is a quite common business case. Creating new projects with the same process configuration from existing projects can be easily accomplished with Configuration Manager for Jira.
< 5 minutes
1 Jira Servers*
New Project Mode
You need one paid license for the Production Jira system.
Accomplishing this use case is quite simple there are two steps:
Creation of snapshot of the project used as a template.
Deployment of the snapshot using the New Project mode.
Source: Create a project snapshot for the project you are using as a template.
Target: Deploy the snapshot
a. Use New Project deployment mode, provide project name and key. They should not match any existing projects.
b. In the Analyze step of the deployment, you will see that a new project will be created and all existing configuration elements will be associated with the new project. No other objects will be created.
Automation of the above steps can be accomplished using the public REST API.