I would handwave it as if in a pony-made world, it's to be expected that equipment from the PHB would have a pony-specialized version. Shields might be strapped to the shoulder or foreleg rather than carried in the hoof, (but rendering said foreleg unavailable for other uses) and two-handed weapons could be so that the stance used to wield it would require both forelegs to be steady, while a one-hander could be used with the mouth or with one hoof without needing to brace with the other. A pony with a sword in its mouth is not an uncommon thing in fanart, at least. Two-Weapon fighting seems a little difficult for me to imagine, though. Not so much as using the weapons, more like how does the pony move around with the weapons drawn. A three hoofed gait is not unusual. Two hooves might be. Unless of course it's hoof/mouth for two "hands". Sword in the fore-hoof, dagger in the mouth.

The fun thing is when you start getting things that exist both for humanoids and ponies in vanilla 5e. Like, does a pony character buy a backpack or saddlebags? Because they're both items in the PHB.

But I figure that if Fallout: Equestria can make shotguns work for ponies, then getting basic fantasy weapons to work is not that difficult, all things compared. How DO pony shotguns work, anyway?

I do kind of feel a little bad for the Changeling suggestions and those got a point knocked off on the review, but then I went and checked and the review was gone. It's now here instead, at least as a voting thread.