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.

This story is a sequel to Equestria: A New Generation

Sunset now joined the new generation ponies as she taught them more about the magic of friendship as they enjoyed their time together, while also seeing how much Equestria developed now that the magic and the magic of friendship returned. And now Sunset helps carried on Twilight's legacy now that Equestria needs to recovered what is lost while also trying to figure out how it came to be and what happened to Twilight and her friends while enjoying time with Sunny and her friends along the way.

To keep in mind, this is a side story that takes place after the movie of MLP: A New Generation, but also in between the Make Your Mark series so this story take place between them.

Image credit goes to Bookhorse125

(Note: the inspiration goes to Phantom-Dragon since he came up with the idea from his last story Equestria: A new generation, so give credit for him for this inspiration)

Sora was an average teenage boy, though average was an understatement. At the age of fourteen, he was thrust into a battle between light and darkness, wielding a mystical weapon known as the Keyblade, saving worlds from creatures known as the Heartless and finding his friends, Riku and Kairi. He has saved the universe many times from the Heartless, saved Kingdom Hearts from being controlled by those with evil intentions, and has made new friends in each world he visited.

However, he fails his mark of mastery exam after almost getting himself killed by Xehanort's younger self, needing to be rescued by his friends as Riku and Kairi become Keyblade Masters. Needing more training before he can retake his exam, Master Yen Sid gives him coordinates to somewhere in the galaxy, though the information on what was there or why was unanswered, obeying his teacher. But as he was close to reaching the coordinates, his own gummi ship, which he crafted on his own while on a break a week prior to his exam's failure, malfunctions for some unknown reason and crashes into the world of Equestria.

With no way to make it back home, and Equestria too far from the rest of the worlds to contact his friends or fix his ship, Sora is stranded on this new world until someone realized he's been missing. Until then, he's going to have to fit in, his magic transforming his body into being a part of the world like in many others he visited in the past, and be patient. Little does he know that there were also dangers that lurked in this world, aside from any Heartless that may appear.

Sora's story takes place after the events of Dream Drop Distance, his adventures beginning in Equestria before the season 1 premiere of My Little Pony: Friendship is Magic.

Kingdom Hearts is owned by Square Enix and Disney. My Little Pony: Friendship is Magic is owned by Hasbro.

EDIT: Those who are new to this story, there are links in a majority of the chapters where they lead to soundtracks of Kingdom Hearts to help build an atmosphere in the story. Sadly, most of them may come up as dead links because those videos had been taken down by the YouTuber for some reason, even if there are some still active by that same person, or they'll be gone as well if they happen again. With how many chapters I've put in this story, and how many links there might be, I don't have the patience to take them down or find new links with the right music I chose for those moments if I can remember which ones. So, up until Equestria Girls: Legend of Everfree (Part 3), ignore the links, as much as I hate to say that with the hard work I've done. Hopefully this crossover will be as enjoyable without music as it keeps on going.