devtrackers.gg
Yes, this was in the announcement back in July and is included in this one. By default the weapons are specific to their factions but you can turn that off.
Correct, you can mix and match. And that's a major part of the fun!
I'll quote the relevant bits from the latest Battlefield Briefing where it's explained in detail:
Characters"Depending on what you chose in the previous section, you’ll then be able to deselect which classes (or 2042 Specialists) are playable. You’ll also have the options to denote which factions show up in-game. The UK, US, and German factions are available for 1942, with the game appropriate versions of the USA and Russia available for the rest."
Weapons:"In total, there are over 75 Weapons available across the entire experience of Battlefield Portal at launch. Now that you’ve chosen your factions, you’ll have the ability to manage what weapons are available. If both teams are from the same era, you can also make use of our unlink teams function to customize exactly which weapons each team is gaining access to."
There's a ton more...
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