Star Wars Battlefront 2 is primarily an online multiplayer game although you can set up battles against the computer and also contains a single player campaign. The campaign is split up into two parts (I believe the second part was free DLC).
You begin the campaign as a flying droid (which is a bit strange), and you have to rescue the main character; an Imperial Commander called Iden Versio. You don't play all missions as her though. On the positive side, this means you get a demo of some of the characters to introduce you to the different abilities and play-styles. The negative is that the characters aren't as developed as you would want, which means when the time comes for the predictable change in allegiances, it lacks the impact it should.
The multiplayer has quite a few different modes, which usually involve large teams of players battling over some objective, respawning in as a different character when you die. Some of the modes include:
Heroes and Villains is a 4 on 4 battle mode but each round highlights a character from each team that is the target, and it is up to your team to take out the target whilst defending yours. In this mode you play as the primary characters in the film, so the Heroes feature characters like Yoda, Luke Skywalker and Rey, and they will battle against the likes of Darth Vader, Darth Maul, and Emperor Palpatine.
Starfighter Assault features battles in space, so you will be flying craft like Tie Fighters and X-Wings, with the Hero characters being crafts like the Millennium Falcon. The Starfighter battles were decent but felt a bit clunky in some ways. I preferred the standard combat.
Blast is a team death-match; 8 vs 8, first to 100 kills.
Strike is another 8 vs 8 mode but gives you objectives like arming bombs or capture the flag-style.
Ewok Hunt is quite scary. Storm Troopers have a flash-light and a gun and wander Endor's moon in the pitch black whilst the Ewok's hunt them down.
By achieving kills, you level up your characters which powers up your abilities or unlocks new ones to use. Most game types allow you to switch characters, and often you will use different types of troopers; assault, heavy, commander, specialist (sniper). When you achieve a certain amount of battle points, then you are allowed to assume the role of a more unique hero character.
The game was heavily criticised for its pricing model, hiding certain characters behind pay-walls and asking for a ridiculous amount of points in order to unlock them. It seems after the backlash, EA have changed it to a fairer micro-transaction model where character are unlocked from the start (apart from the recently introduced General Grievous), and you just pay/use in-game credits for cosmetic unlockables; skins, taunts and victory poses. You get a some credits for playing each day, obtaining set achievements, daily achievements, and your performance in each match you play.
I'm not great at these types of games but I did wonder if players had a better advantage by having access to abilities I didn't. I was late to playing this game, and they would already have the advantage of game experience and knowledge of the characters and maps. Having extra abilities as well does skew the difficulty.
The core gameplay is actually very fun, and Star Wars fans will obviously enjoy it. I think it helps to have knowledge of Star Wars so you can quickly recognise who is a threat. There are indicators over your team member's heads and sometimes enemies, but with the constant switching of sides, it was hard to remember which colour represented my team. There can be times where it is a little too hectic. Some modes allow up to 40 players, and putting them in certain areas means it's constant laser fire and explosions and it's hard to work out what is actually going on.
The graphics and sound design is very good, although some maps have a few areas where the lighting is very odd. It could be a bug in the game engine because I have seen similar lighting in FIFA.
Currently, (November 2018) the game is being supported with new content like the new Clone Wars update, and it still has an active fan-base. So newcomers are still fine to join in, but you will have the disadvantage that the majority of players will be at a higher level of experience and skill.