In case you need to test multiple themes with same plugin you are higly likely create a multisite for comparison or ease of testing
Install WordPress Importer plugin
wp plugin install wordpress-importer --activate-network
Get Latest xml file from Theme Unit Test page
Change to Upload directory
wget https://raw.githubusercontent.com/WPTRT/theme-unit-test/master/themeunittestdata.wordpress.xml
Now use this following command
wp site list --field=url | xargs -n1 -I % wp import ./themeunittestdata.wordpress.xml --authors=create --url=%
