It's very much the same planet. It orbits the same star and it has the same moon. But with different landmasses and nations, the creator of the story gets to take many liberties. The use of a Fictional Earth means that past and present real world history doesn't have to affect the story and absolutely anything can be made up. The story's nations may have real world counterparts. These worlds will usually have real world physics, but not always.
The planet has to be identified as Earth at some point, otherwise you're just dealing with a Constructed World that may or may not look like Earth in some aspects. Alternate History settings that are geographically different enough may overlap with this, if the country or continent boundaries changed, especially after a traumatic event.
Compare Earth All Along, where a planet seems alien at first but turns out to be a version of Earth. Contrast Earth Drift, where a setting starts as Earth but gradually becomes a fantasy world as the series goes on. Like Reality, Unless Noted is when the difference with our Earth is minimal and mostly about events and characters.
- The world of Attack on Titan seems to be an Earth that is upside-down.◊ The island of Paradis, where most of the main characters live, is Madagascar, and Marley seems to be mainland Africa along with most of Europe and the Middle East.
- Dragon Ball's Earth is very different from ours. The world map◊ shows a huge continent looking like China note and Funny Animals live alongside humans. It is divided into 43 sectors governed by a King of the Earth. Also the Moon seems to have at least a thin atmosphere.
- The setting in the Naruto franchise takes place on an alternative Earth, and even its sattelite is still called "Moon".
- One-Punch Man is set on a planet called Earth, but it looks totally unrecognizable from the real world. The whole series takes place on a Pangea-sized supercontinent shaped like Japan's Saitama prefecture, divided into 26 city-states each named after letters of the English alphabet, and that's just the beginning of its differences.
- The DCU seems less a fictional Earth and more a fictional America, with many fictional cities inhabited by various heroes, including but not limited to Metropolis, Gotham City, Central City, and Coast City to name a few. Though you do get other fictional places popping up like Themyscira and Atlantis.
- Marvel Universe does indeed take place on Earth, but also features a number of fictional countries, nations, and landmasses. Among these include: Wakanda, which is a technologically advanced African country that's home to Black Panther with its exact location varying between sources. Latveria, a monarchy nation ruled by Doctor Doom as his personal kingdom. Atlantis, the mythical undersea world.
- While it's never clarified if Frozen's fantasy kingdom of Arendelle is in Norway, a part of Norway, or is a fictional country (or city-state) that just resembles Norway, the Christmas Special Olaf's Frozen Adventure shows Norway as existing within the world. Frozen Fever also shows that they're set in an alternate version of Europe.
- The Grand Budapest Hotel is set in the early 1930s and mostly seems to conform to 'our' Earth in geography, technology and culture - there are references to Europe, South America, the Roman Catholic Church, Saxony and the French and German languages are both clearly spoken at various points. However the story is set in a fictional European country (Zubrowka) and notes the existence of other locations that are also either completely fictional (Zero's implied Middle Eastern or North African homeland of Aq Salim al-Jabat) or imply considerably divergent histories at some point (the "Maltese Riviera" and "Dutch Tanganyika".)
- According to Takeshi Shudō's novels Pocket Monsters: The Animation, the Pokémon anime takes place on a futuristic Earth where Pokemon are aliens who replaced most of the wildlife. Also Hollywood was in Kanto. This made sense back when Kanto (named after Kanto, Japan) was the only known region, less so after the Earth Drift that started with Generation II. How canon the books are compared to the anime is debatable anyway, since they're a mix of behind-the-scenes details, commentary and Alternate Continuity.
- J. R. R. Tolkien's Arda is meant to be Earth in a fictional ancient time period. However, its geography is clearly fictional.
- Harry Turtledove's Atlantis series is like our Earth, except the east coast of North America broke off millions of years ago and became its own continent, unsettled and devoid of land mammals until its discovery in the 1400s. Despite this, history continues as normal until Atlantis is discovered, with at least one Native American group living in the same geographic location despite the radically different geography.
- French-Canadian children's fantasy series Amos Daragon lives and breathes this trope, with the world being very different from Earth geographically and populated by all manners of mythological creatures from all around the world while also featuring real-life civilizations and peoples like Sumerians, Dogons and Vikings and gods like Odin and Seth.
- The Deltora Quest Shared Universe takes place on the "World of Deltora" with hundreds of fictional islands including Deltora, Maris, and Dorne all located in seven seas. While humans are a predominant species there also many more fantastical creatures from gnomes, dragons, Fish People, and Capricons to name a few.
- Downplayed in Kushiel's Legacy: there are fictional countries, but the map is almost identical to Earth's except for a few alterations thanks to more actively involved divine forces in its history. Real countries are known by different names, though. It also overlaps with Alternate History, from the fall of The Roman Empire onwards. Significantly, the equivalent of the English Channel has the islands of the Three Sisters, where the Fallen Angel Raziel is bound beneath the ocean.
- A Memoir By Lady Trent is set in a fictional world, but the countries correspond to real-world ones (Scirland is Britain, Bulskevo is Russia, Akhia is Arabia and Egypt, etc.).
- The map at the front of Terry Pratchett's Nation shows that while this is clearly a version of Earth, and very similar to our Earth in the 19th century in many ways, it is not our Earth in terms of either political geography (The Re-United States) or physical geography (the two landmasses of Nearer Australia and Further Australia).
- In the world of The Rithmatist, North America consists of sixty islands instead of a continent, all of which are part of the United Isles of America. We don't hear much about the rest of the world, though the sequel will focus on Central and South America.
- The world of A Song of Ice and Fire is based on Earth with some key differences. For example, Westeros basically corresponds to Europe both culturally and in size, but is similar to a re-arranged map of Britain. Essos is Asia and Sothoryos is Africa. There is also a fourth continent called Ulthos, which, judging by what little description we know, may be the equivalent of Southeast Asia/Oceania. Some fans speculate that another continent corresponding to the Americas is yet to be discovered.
- The world of The Wheel of Time is strongly implied to be a distant and different future Earth, as the setting has an Eternal Recurrence of seven Ages that fade into history and come anew. Thanks to the Breaking of the World, an ancient supernatural cataclysm that rearranged the continents, the maps look completely different; but there are quite a few references to Earth history and myth, as well as a few ancient artifacts that originate in present-day Earth.
- 7th Sea: Théah is a facsimile of Earth in the 17th century from the abundance of fantasy counterparts to real-world countries to even its Significant Anagram name.
- Warhammer: The world map is clearly based on Earth's◊, though it has a few extra islands and geographical features Earth does not, such as North America being either frozen tundra or burning desert, Africa being split in two by a mountain range, and Antarctica being a warm wasteland populated by beastmen. In early editions, Warhammer 40,000 was set in the far future of Warhammer Fantasy, but they now exist in separate realities linked by the Warp, and 40K's Earth is now our far future.
- Mega Man Battle Network: In the WWW lab in the first game, a screen of the world map indicates that the Battle Network series takes place basically on Earth◊ (in keeping with its connections to the Classic series). Battle Network 2 showed a world map in one scene◊ that looked nothing like Earth however, and introduced fictional countries. Battle Network 4 burned that bridge with a vengeance, introducing an all-new globe◊ whose landmasses only vaguely resemble our Earth's at best.
- Interestingly though, Spanish and English are mentioned as languages in Battle Network 3, which is well after the series established the games were set in an alternate Earth, even though Spain and England presumably do not exist in this world.
- Illusion of Gaia: Despite historical landmarks from the real world existing, and certain historical figures like Columbus being mentioned, the landmasses of the world are radically different, and many of the locales are completely fictional. Subverted that it's actually a corrupted version of our Earth, and after you defeat the comet, the Earth regains its natural appearance, making this trope actually Earth All Along.
- Ace Combat is a prime example of this trope. It's Earth in every possible way except for landmasses and nations. You can even tell what real world counterparts the nations are based on. It has an Antarctica barely different from the real one, as well as landmasses resembling Greenland and New Zealand. It even has its own Pacific and Arctic Oceans. Almost all the aircraft used in the game exist in reality, aside from the fictional superplanes.
- Civilization always takes place on Earth and uses its cultures, and most of the games have an option to replicate a real world map, but it's also possible to use a randomly-generated map that looks nothing like the real Earth.
- Dragon Master: Seems to be in effect given that the map shown during intermissions between fights lacks any similarity to any areas around the Pacific Ocean and especially not the world map.
- Downplayed and Played Straight at the same time in Europa Universalis IV due to Random New World mechanic. Downplayed in terms of scale - this option completely changes the appearance and geographical location of all lands on both sides of Eurasia, while Eurasia itself, as well as Africa and Australia with most of Oceania, remain unchanged. All other aspects are played absolutely straight: everything that is America in our world will be different, starting from landscape or climate and finishing with local peoples. Regarding the latter, you can meet disunited separate tribes with significant technological backwardness, which will make the generated New World quite similar to the real analogue. However, map can be generated with allowed fantasy scenarios, which can lead to a meeting with the mighty and united Native American empires, that will not be inferior at all to aliens from overseas, or with completely fantastic formations such as Lost Templar fleet, Lemuria or even successor state of Atlantis.
- The world of Final Fantasy IV is named Earthnote . The landmasses are definitely not ours◊. The surface where most people live is named "Overworld" and the inside where Dwarves live is the "Underworld". Fu-So-Ya also says that the Lunarians originally came from a planet that orbited between Mars and Jupiter before it was destroyed.
- The world of Pokémon is an interesting case. It was identified as Earth in the first generation, mentioning real world events and locations in Pokedex entries and naming Kanto after the actual Kanto region of Japan. However it is geographically completely different and real world mentions were dropped from Generation II onwards. However, every region in the main series is a Fantasy Counterpart Culture of a real place. The implication seems to be that the Pokémon world is a Fictional Earth that doesn't really mention the Earth part anymore.
- Inspired by Ace Combat, Project Wingman takes place in a world that is mostly like Earth, but over four centuries after a global tectonic disaster known as the "Calamity" which reshaped continents and created new islands and seas.
- Some of the Sonic the Hedgehog games takes place on Earth, however the geography is completely different and countries are replaced with fantasy versions.
- Super Mario Bros.: In Super Mario Odyssey, Mario travels a planet that resembles Earth, but with different landmasses and kingdoms inspired by real countries. The Mushroom Kingdom (the main setting of most Super Mario Bros. games) is found on a landmass that resembles a 1-Up Mushroom. The continents resemble the Earth's at some point in history, with three looking vaguely like Pangaea, Laurasia, and Gondwanaland. There's also no land at either pole, with the landmass the Snow Kingdom is on ending close to the north pole, and the south pole being completely covered in ocean with the nearest land being thousands of miles away.
- The Earth of Avatar: The Last Airbender is divided into four elemental nations. It is drastically different in terms of continent placement, with a landmass at each of the poles, and the Earth Kingdom being possibly bigger than our Eurasia. There's no equivalent for the Americas, Australia, and other continents.
- Steven Universe takes place on an alternate Earth with a number of subtle differences in the US, for example, money has diamonds on it instead of Presidents' faces, and the center of the film industry is in Kansas. More importantly, the world map is quite different: part of Africa is attached to South America, and large amounts of real life landmass is instead covered by the ocean, including the majority of northern Asia. The latter is implied to be a result of the Gem Homeworld's Hostile Terraforming. The former seems much older.
- While almost nothing about this is indicated in its mother film (although is probably a result of Tangled being established to share its universe with Frozen, which has indicated this), Tangled: The Series takes place on an alternate Earth. A Distant Reaction Shot in the Grand Finale also shows that the series is set on a landmass that highly resembles Europe and that Corona is located where Germany would be.