It's tradition to trivialize FromSoftware's notoriously difficult games by using the dirtiest, cheesiest strategies and equipment imaginable, and Armored Core 6 players have taken this to a new extreme by literally giving everything in the game both barrels, by which I mean two Zimmerman shotguns.
I haven't seen a weapon consume a community like this since Elden Ring's hilariously broken Rivers of Blood katana, which ended up eating several nerfs in the game's first year. The SG-027 Zimmerman shotgun is running rampant in the newly revitalized Armored Core community, decimating campaign bosses and PvP opponents alike. With one in each hand, virtually nothing can stop you.
What makes the Zimmerman so good? Well, it has extremely high effective range, best-in-class damage, heavy stagger, solid direct hit damage, and a forgiving reload time as well as high total ammunition. You also unlock the Zimmerman pretty early on, and it isn't a super heavy or energy-intensive gun, meaning it can slot into most builds fairly easily. This makes for an easy-to-use DPS monster that's good in close- and even some medium-range engagements, and it didn't take long for players to figure out how strong a pair of Zimmermans can be.
The Zimmermans aren't alone, to be fair. Miniguns, stun needle launchers, and Songbird rocket launchers have also eaten a sizable chunk of the meta by doing absurdly high damage or being criminally easy to use. But the Zimmermans are such lightweight and dominant main-hand weapons that many players are already expecting them to get some sort of nerf in the future, if only to push a little diversity into the meta. It'll be interesting to see how closely FromSoftware balances Armored Core 6 as the dust settles.
I avoided any sort of Armored Core 6 PvP or meta research until I'd beaten the game three times, and even in isolation I fell to the allure of the Zimmerman. I ended up pairing it with a laser lance in the build I assembled after finally putting down the laser sword, the real best weapon in the game, and I can confirm that this shotgun absolutely slaps. And look, I don't make the rules: if a shotgun is so oppressive and popular that it's been turned into an anime girl by a fan artist mad with power, it's probably getting nerfed.
In defiance of FromSoftware, Armored Core 6 players are making their own versions of the game's faceless characters, and if you guessed half of them are now anime waifus, you are correct.