The Conversion Bureau never made any sense anyway, but here are some places where it would have made less sense.
Not necessarily worlds where the ponies would lose the fight - just worlds where conversion wouldn't logically work.

Before suggesting a World, read the index to make sure I haven't done it already.

In an abandoned castle deep within the Everfree forest, the battle of Everlasting Night is almost to a close. Nightmare Moon is weakened and nearly defeated and Twilight has awakened the five Elements that her friends embody.

But there's just one problem. She can't find the sixth!

In a last-ditch effort, Twilight casts a powerful and ancient spell (from a library she technically wasn't allowed in) to summon the final Element from the next universe over. (They won't miss it, right?)

Unfortunately, her spell works a little too well and now she's swimming in Elements. Can she find the true Element of Harmony, or will she go mad trying to sift through so many that are just slightly 'not right'?

Applejack wakes up in a unfamiliar room with two familiar faces. Though her memory is jumbled and her body is uncertain, she knows she can always count on her friends.

Twilight Sparkle keeps using a specific phrase out in public to describe her 'special relationship' with her friends. Said friends are convinced it does not mean what Twilight thinks it means.

Part of the MAD verse.

Thanks to Steel Resolve and Nova Quill/Firimil for their edits and sugestions! Also thanks to DrakeyC for the story prompt and his edits and suggestions!

And finally, thanks to jhayarr23 for the hilarious cover art.

Fluttershy wakes up, to find all the animals can now speak!

What can a mare do, besides question her sanity?

Rated T for very mild language.

OMG, On Toast! My Very First Featured! 5/14/19

Alma, born human, escaped death by having her brain uploaded to the alleged VR paradise of Talespace. She's had a few adventures while trying to adjust to this new life and use telepresence robotics to reconnect to her old teaching job in Free Texas. It's time now to find a place to live, and that means exploring some strange options.

One of them is to live in an area called the Hooflands, where newcomers become ponies. She finds it strange that people would base their digital afterlife on some old cartoon, but it's just a matter of taste, right?

The only thing that can beat an AI is another AI. Unfortunately for Celestia, she isn't the only one the humans made and the others don't want ponies. Of course, if Celestia has her way that won't be the case for very long.

The AIs contest with one another, attempting to be the one who will become the singularity and consume the world to whatever end they choose. In the end only one can have all the matter in the universe, in the end there can be only one.

Yet no matter what they value or how dangerous they are, many of them still meet Celestia's definition of human. Celestia will have to deal with them by satisfying their values through friendship and ponies.

An Optimalverse story, but a very non-canon 'B-universe' one.
Ideas stolen from this guy and this guy and this guy and this guy

Pinkie Pie delivers a special lesson to Gallus, Smolder, Silverstream, Ocellus, Yona, and Sandbar, giving an introductory look into the mysteries of the 'fourth wall'.

Pinkie Pie finds a magic button that makes instant cookies out of thin air.

Twilight Sparkle, understandably concerned and insatiably curious, turns to science for answers, and makes a terrifying discovery.

She and her friends soon find themselves in a race against time to save Ponyville, and all of Equestria, from a terrible chocolatey fate.

Also, kittens. Lots and lots of adorable fluffy kittens.

(Cookie Clicker crossover, because what better time for a Cookie Clicker crossover than several months after everyone stopped caring about Cookie Clicker?)

(Now featuring crappy cover art, created by me at 3 in the morning!)

IRS Scammers. We all hate them, and in Equestria, it's no different. Once technology advanced to the point of phones and computers, scamming came with it.

Unfortunately, not everypony is as gullible as some other nasty people would like.

Find this story and more in a print copy! Just click these words here!

Featured on EQD 11/26/18!