Hello,
If you mean presets and not audio samples, then you can import them in Analog Lab.
You can't load audio samples into Analog Lab. Analog Lab use sounds made in Arturias full software instrument applications.
It is possible to load audio samples into individual full instruments that use samples, for the functionality the samples are used for in that application. They are used to make sounds.
Only some applications use samples.
A controller only triggers external sounds. It has'nt any onboard sounds.
If the mp3 is a full track, then you are on the wrong track. Then you shall use a host like a DAW or a simple audio file player of some kind. That depends.