If you want to connect your AirPods to Ubuntu 19.10 (Any distro that uses bluez like Fedora, Manjaro, KDE Neon, etc.), it won't work out of the box. But the solution to this is quick and easy.
We need to edit the Bluetooth configuration file:
sudo nano /etc/bluetooth/main.conf
Look for “#ControllerMode = dual”. It's at the bottom part of this file. We need to uncomment this line.
Then restart Bluetooth and pair normally:
sudo systemctl restart bluetooth