The community is pretty active, especially on PS4.
The game is still being supported with updates happening about every month or two, but all the balance patches are centered around PC gameplay instead of Console gameplay.
The most populated modes (at least on PS4) are Dominion (4v4 capture objectives mode), Duel (1v1 fights), and Breach (4v4 castle siege mode). Out of those 3, Dominion is the most populated and has the fastest queue times.
All game modes can be played PvAi except for Ranked Duel. Ranked Duel unfortunately isn't great and most people playing it are only doing it for cosmetic rewards.
There are 5 DLCs: Year 1 which gives you 6 heroes, Matching Fire Expansion which gives you 4 Chinese heroes and the PvAi mode Arcade, Year 3/"Year of the Harbingers" which gives you 4 heroes, Warmonger DLC, and finally the current battle pass for this season. Out of everything I listed, only Arcade is locked behind DLC. All heroes can be bought with in game money called steel that is earned by completing orders and playing the game.
Progression mostly works on a rep system. Every 20 levels on a hero, you will get reset back to lvl 1, but that hero will gain a rep. The more you level and rep up your hero, the more cosmetics you get to customize your hero. You can also buy outfits (consisting of effects over your hero, patterns, and decorations to your helmets/pauldrons) as well as executions, emotes, and other things in game. You will have to have that hero unlocked, but that Vanguard's start off free and the starting cast is extremely cheap to buy (can be unlocked after 1 order is complete). You also can't play any DLC heroes until you unlock them. Customization is pretty limited however even with all that said.
No crossplay although there have been rumors of it coming to the game for a long time now.
If you do pick up the game and have any more questions whether that be character related or not, me or someone else could probably answer it here. There's also a Discord that focuses entirely on helping new players and I or a guy here called arr_me_maytee could give a link to if you want.
CEO: "You know, I use to own a Corolla-"
Intern: "I know that... It's in the book."