Star Wars Battlefront 2 was initially released in 2017. The game received mediocre reviews, with many unhappy about the progression system and the micro-transactions. However, EA surprisingly listened and released consistent updates to the game from 2017 to 2019.
The game has since stopped receiving significant updates, and the game now is significantly better than it was at release.
The free version of the game you can claim on the Epic Games Store is the Celebration Edition. This version comes with all of the customizations and additions to the game from launch until December 20th, 2019.
You will be able to claim the game for free from today, January 14th, until next Thursday, January 21st. All you need to do is head over to Star Wars Battlefront 2's Store Page.