The MFD or "head" has to be compatible with LiveScope; there's a chart on the Garmin website. These all have a different connector for the Panoptix LS black box on the back, so yes, you can have a regular 2D/dv/sv transducer and Panoptix LS both on one head, with no y-cable.
Sonar Transducer | Panoptix™ by GARMIN