https://www.pcgamer.com/battlefield-5-will-launch-with-two-playable-factions-more-will-join-as-the-war-unfolds/

Electronic Arts laid out its long-term plans for Battlefield 5 in a new blog post on the Tides of War, the name it's using to describe the "evolving journey" that players will take through the course of the Second World War. Players will create Companies of soldiers, weapons, and vehicles, all of them customizable and available in all multiplayer modes and Combined Arms. Players can have one Company per faction, beginning with the British and Germans, the two multiplayer factions that will be available at launch. 

Soldiers will be broken down into four basic classes—Medic, Scout, Support, and Assault—that can be further customized with loadouts and cosmetics. Earning experience through gameplay will unlock Archetypes, which are essentially specialized classes: The Support soldier can opt to be an Engineer or a Machine Gunner, for instance. New Archetypes will be added as the Tides of War rolls on, and "exotic Archetypes" like Paratrooper Recon will enable even more focused specialization.