https://www.pcgamer.com/play-overwatch-for-free-this-weekend/

Thursday was Overwatch's second birthday, and you can celebrate in an anniversary event complete with a bunch of new skins, a new deathmatch map, and more. It's also having a free weekend, which is now live and runs until Tuesday.

As long as you have a Battle.net account then you can play, and you get access to all 27 heroes, including Brigitte, the game's newest character. You can jump into Quick Play, custom games or the game's Arcade (which has modes that mix up the rules), and play on all 18 maps. You'll unlock cosmetics and emotes for your heroes, level up, and earn loot boxes. Basically, it's the whole game, without competitive play. And if you want to buy it after, then you keep all your progress.