lord of the rings - How did Thranduil know about the 'infamous' Strider when the latter was only 10 during the Battle of the Five Armies?

The Jackson movies are operating on a different timeline to the books.

Some examples:

• The White Council don't know about Sauron's return until the time of the Hobbit movies.


• Mirkwood not becoming corrupted until the time of the Hobbit movies.


• The condensed timescale between Bilbo's birthday party and Frodo's leaving of Bag End.

What is certain is that at least 60 years pass between the Hobbit movies and the LotR movies, per Gandalf's words (source):

For sixty years the ring lay quiet in Bilbo's keeping, prolonging his life, delaying old age...

Given in particular the condensed timescale in my third example, it's likely that not much more than 60 years pass, so therefore - and in movie-canon - Aragorn wouldn't have been 10; he would have been about 27/28.