Hey @drumsruan, welcome to the forum!
Multiline for chords isn’t available yet, but I’ve recently added support for this in the latest beta, AbleSet 2.6.0-beta.3. This should be released in the coming weeks.
If you’d like to test this already, feel free to download the beta. I’d recommend not using this on stage since it might contain bugs I haven’t found yet, but you can always downgrade to the latest stable release by downloading it from the AbleSet website.