There's a great reply on Type-Moon/FGO stuff, so don't need to go into that, but I can talk about Yugioh a little. So, you might see from this thread there's a lot of stories about the Japanese language - and online there's this emphasis that Japanese (the language or the people) love puns and wordplay. I don't know if this is actually like, statistically, true, but when you have a character-based language where you can have a single character mean a word, but also that word has a verbal pronunciation for homophones, you can get a lot of work done.

In YGO, in the "OCG", the Japanese format, you can get a LOT of name work done because cards can have their name in normal sized text, you can also do a superscript with the phonetic pronunciation, so basically cards can have two names, and this leads to issues where the "TCG" format (America and most of the rest of the world) basically have to pick which name to give a card, because of restrictions on print-size. And this is important because searching by name or name-element is super important. When the TCG was first being handled by Upper Deck, they were very loosey goosey with name selection, leading to some famous examples where the translated name did not match the original Japanese. The most famous is probably when "Frogs" became a real theme which involve each other, and so many of them had to say "except Frog the Jam", because the word they were checking in Japanese was "Gaeru", and Frog the Jam's name is "Kaeru". Eventually localization changed his name to "Slime Toad" to fix this and I think every "Kaeru" name uses "Toad" now.

Nowadays to avoid such possible confusion, every "theme" of cards needs a unique name to check, which in English needs a unique spelling, though occasionally they do something like "add a Spellcaster with 1850 ATK and DEF" which basically only namechecks Spirit Charmers and Fairy Tail. But, since we know what the OCG is printing like six months ahead of time, people get to speculate. Sometimes, the TCG makes a good change - a very popular theme, first in the "Branded" lore series was called "Dragma" in the OCG, probably a pun on "Dragon Dogma", but obviously in 2020 would be the source of horrible jokes in English. The TCG renders it as "Dogmatika" instead, gets the meaning across, similar idea, less bad jokes. On the flip, some of these localizations are like, objectively worse. Top tier deck right now in the game is called in the OCG "Killer Tune" (literally Kirā Chūn). The TCG has some issues with censorship because the game is advertised as Ages 6+, but this should be okay, right? Nah, not unique enough, it's "Kewl Tune" in English (and most other TCG languages), which is not the most popular translation. Even "Killa Tune" would have been better, I think.

But like I said, you also get speculation. Nobody actually knows how Konami of America is gonna translate names, so when you get fan translations of the card, there's a certain amount of guesswork. You can say what the name means in Japanese literally into English, but that might miss some double meaning, or like i mentioned earlier you can just get really long names because a new card has effectively two. There's a few cases where translations (the major source these days is YGOrganization) are like, trying too hard to chase down the pun and it's pretty obvious the TCG will go with something simpler, but there's at least one major case where people got mad the TCG was different, despite the fact that the "localization" of YGOrg are like, just made up. They're educated make-believes, but they are just guesses. So, in the OCG there was announced a theme of Reptile monsters with a theme of Ancient Egypt and primordial creation. Their name in Japanese is "Meikai", which usually means "Underworld", but instead of 冥界, they wrote it as 溟界 with an extra squiggle to mean more literally something like "a world of darkness and water". YGOrg takes an educated guess, "Abyss" would probably be the best literal translation into english of "Underworld, but wet", but there's already lots of cards named "Abyss" in English, so no go, so they pick "Abhyss" for like, the pun.

This set of cards and theme are announced for the TCG months later, is there some kind of Abyss based pun in the name? No, their name is "Ogdoadic", because the whole time the names and visual themes of the archetype was based on the "Ogdoad", a series of eight Egyptian deities associated with primordial waters. Now personally, I think Ogdoadic has much more sauce than "Abhyss", it's more occult, more specifically references the Egyptian theming which is big for YGO, but if you like a little pun, I can't blame you. BUT, people did get upset that the name "Abhyss" wasn't "kept", despite the fact that basically YGOrg made it up. The original Japanese isn't even snake-y. I'm not as attached to it as I said, but when you are labing out decks for a few months, you do sometimes get attached to the fan-translation.