Note This was a quick throw together works for me fine :) export your jira issues as xml and this will import into github issues. Requires Github Token (requires repo access)

Exporting Jira issues
Go to jira issues & filters -> search, filter out the issues that u want to import into your github project, then export/save as a xml file...

Importing Jira issues
git clone git@github.com:lukesUbuntu/jira-2-github.git

cd jira-2-github

npm i

npm run build

cd dist

edit config.json and update with required details

{
    "githubToken": "YOUR_GITHUB_OAUTH_TOKEN",      // https://github.com/settings/tokens/new (requires repo access)   
    "githubUsername": "YOUR_GITHUB_USERNAME",      // github username
    "githubRepo": "YOUR_GITHUB_REPO",              // repo you want to import issues to
    "jiraXmlFile": "FULL PATH TO XML FILE",        // the xml file you exported the issues to
    "dryRun": false                                // test run first to see imported issues
}

node app.js

you will get a console.log of what would be imported, if happy edit config change dryRun to false and then node app.js

Going to make a electron deskop app for easy importing and repo selection