BluetoothConnector 
Simple macOS CLI to connect/disconnect a Bluetooth device. I made it to easily connect my BeatsX earbuds (I thought the W1 chip would make the switch from my iPhone to my Mac seamless, but we're not there yet, apparently). There's probably a program that already does this but I didn't find it.
You can download a compiled version here: https://github.com/lapfelix/BluetoothConnector/releases
If you have issues running the compiled binary (permission denied error), try running this command in Terminal:
chmod +x /path/to/BluetoothConnector
Installation
Homebrew
brew install bluetoothconnector
Mint
mint install lapfelix/BluetoothConnector
Manually
swift package update
swift build -c release
mv .build/release/BluetoothConnector /usr/local/bin/BluetoothConnector
Usage
Running
Replace 00-00-00-00-00-00 with your device's MAC address. You can get it by alt-clicking the Bluetooth menu icon or by running BluetoothConnector without any arguments
To toggle the connection (connect/disconnect) and be notified about it
BluetoothConnector 00-00-00-00-00-00 --notify
To connect and be notified about it
BluetoothConnector --connect 00-00-00-00-00-00 --notify
BluetoothConnector -c 00-00-00-00-00-00 --notify
To disconnect
BluetoothConnector --disconnect 00-00-00-00-00-00
BluetoothConnector -d 00-00-00-00-00-00
Notification Center
You can have BluetoothConnector send a notification to say what it did (connect or disconnect), if the action succeeded or get an error description if something goes wrong
BluetoothConnector 00-00-00-00-00-00 --notify
To reduce Notification Center pollution, I'd recommend turning off "Show in Notification Center" for the Script Editor app in the Notifications system preferences:
With Automator to bind a shortcut to it (this is how I'm using it)
I included an Automator workflow service that calls BluetoothConnector from /usr/local/bin to make it easier to run BluetoothConnector with a keyboard workflow (this is how I'm using it).
Then open the Automator workflow and you should get a prompt to install it (don't forget to change the MAC address).
To bind a shortcut to the Automator service, launch System Preferences and Go to Keyboard > Shortcuts > Services, find your service and add a shortcut to it.