I thought you used to be able to share extension attributes but I do not remember now.
I got the basis of this from an older EA located here
[McAfee Check EPO Agent Version]https://www.jamf.com/jamf-nation/third-party-products/files/525/mcafee-check-epo-agent-version)
#!/bin/sh
#Reports the version of the McAfee EPO Agent installed on the client computer.
#Data Type in JSS for this script should be set to: string
Version=`cat /etc/cma.d/EPOAGENT3700MACX/config.xml | grep "<Version>.*</Version>" |sed -e "s/<Version>(.*)</Version>/1/"|tr "|" " "`
echo "<result>$Version</result>"
fi