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I'm Mr. [Future Pop Culture Reference] - using a pop culture reference as a fake name.
A Little Something We Call "Rock and Roll" - probably the closest to what you are describing.
Been There, Shaped History - If the culture takes off because the time traveler introduces it.
If none of these are what you're looking for, try Time Travel Tropes.
Looked before, looked again, nothing applies AFAICT. Here are a few examples:
- Quantum Leap:
- Sam leaps into a magician in 1974. His daughter/assistant menitons that they have an auditon for "Bill Bixby's TV show." Sam replies with a reference to The Incredible Hulk but she's talking about Bixby's previous (current, to her) TV series The Magician.
- in "The Leap Back" Al leaps to 1945 and makes a passing mention to boxer Mike Tyson. The people he's talking to have no idea who that is.
- Voyagers: In The Boxing Episode which takes place in 1938. Jeff is trying to encourage Joe Louis to do an old fashioned training montage.
Jeffery: Haven't you guys ever heard of Rocky Balboa?Lackey 1: Who?Lackey 2: The explorer? [thinking that Jefferey is talking about Vasco Balboa]
- Doctor Who: In "The Shakespeare Code" when Shakespeare is stuck on a rhyme in an impromptu spell, Martha suggests the word "Expellaramus!" Shakespeare goes with it because it rhymes and scans, but he clearly has no idea what it means.
Can also be the In-Universe form of Orphaned Etymology (usually Played for Laughs)

Is there a trope for a time traveler note dropping pop cultural references that from the perspective of those he's talking to are meaningless, because they haven't happened? Happens regularly on Quantum Leap and at least once on Voyagers!. Doctor Who must've done it at least once but I can't recall one.
Edited by randomsurfer