Settings are available from X-Plane's menu:
Plugin > LiveTraffic > Settings.... The "A/C Labels" tab allows to select, which information will be shown in the yellow labels with the aircraft. It also defines the window title of the A/C Info Windows.
Just select the information you want to see. The label is put together in the order as listet here, static data first, then dynamic, top down.
ICAO A/C Type Code
Unique, ICAO-defined identifier for the type of aircraft, like A388 or SR20. See the ICAO DOC8643 aircraft type designators for a list.
Any A/C Id
The first non-empty field from the following list: Flight Number, Call Sign, Registration, Transponder Hex Code which happen to be exactly those fields used in an a/c search in the a/c info wnd.
Transponder Hex Code
Unique identification of an individual plane, or, strictly speaking, its transponder. Used throughout many database for airframe identification.
ICAO Operator Code
ICAO-defined identifier of the operator of the aircraft, often an airline.
Call sign used in radio communication. For airliners this often gives away the flight number (here: LH773), but this is just convention and no guarantee.
Flight number. This is community-maintained data from the tracking data and might be inaccurate.
Departure and arrival airports.
This is community-maintained data from the tracking data and might be inaccurate.
Dynamic Data, updated every second.
Note that all this data refers to LiveTraffic's modeling. This is supposingly close to reality, but not real.
Current flight phase like Take Off, Climb, Cruise, Approach...
...in degrees. Note that LiveTraffic does currently not distinguish between track and heading in flight.
Height above ground level in feet.
knots over ground.
ft/min vertical descend (negative) / climb (positive) rate.
This section defines the colour of the aircraft labels:
Label colour is defined by the Flight Model and may vary per aircraft: By default the model defines:
Huge Jets: red
Business Jets: light blue
GA and smaller: green
all others: yellow
One colour is defined for all labels
The text field next to the Fixed check box defines the color in form of a hex RGB color code. The 4 buttons provide standard values for yellow, red, green, and (light) blue. But you can enter any value manually. Check out color picker web sites like this one for inspiration.
This defines, when labels appear. By default labels are always shown.
Show labels in external views (i.e. outside the cockpit)?
Show labels in internal views (i.e. when sitting in the cockpit)?
Show labels when VR is active?