Yes, MX Master 3 for Mac is compatible with the Logitech Unifying receiver.
The Logitech Unifying wireless receiver is a USB dongle accessory that allows you to connect the mouse to the computer using USB. It can be useful if you prefer to avoid or cannot use the direct Bluetooth Low Energy connection.
It can be purchased here on the Logitech website or in selected retailers.
You will need to install Logitech Options Software and click on “Add Devices” in order to pair your MX Master 3 for Mac with the unifying receiver. You can download Logitech Options by clicking on the Download link in the left menu panel.