It's not slang, as it can be used comfortably in very formal speech. Instead, I would call it a metaphor.

"Trivia" is used most often in an "uncountable" way, just like "wisdom" and "water". It makes sense to be "filled with" or "full of" any of these things. "Filled with" would sound better than "full of", but "full of" is correct. "Triviality" is an equivalent word that is used in a "countable" way. To use it, you would need the plural: "You are filled with trivialities".

Greenland fish it lives about 200 years in the Arctic.

It's not exactly slang, but it's very informal, and often slighty satirical. You could say someone is full of trivia, knowledge, wisdom . . . pretty much any quality you can think of.