An interesting twist: Leo's name is translated to Leon for the English version of the remake. Make it the other way around, and you get a Nohrian prince: Leo's the English name, Leon's the Japanese name.
The name of one of the starting villagers in the Japanese version translates to Robin, which is also the English default name of the Avatar in Fire Emblem: Awakening. The English version of Echoes: Shadows of Valentia changes it to Tobin.
One mercenary is named Kamui, the default Japanese name of the Avatar from Fire Emblem Fates. Since the Fates character was the one renamed in English, Gaiden Kamui retains his name across languages.
The remake adds yet another villager. This one's named Effie which is also the English name for Elise's retainer in Fire Emblem Fates. The English version has changed her name to Faye.
Game files show that alcoholic items would have originally been consumable by characters over the age of twenty, with each character being assigned an age in their internal data. In-game the alcohol can only be offered to Mila statues to restore fatigue and Mila's Turnwheel, and the ages are never given.
Several characters have mourning quotes for finishing a battle after Celica is killed, which, in the final version, is an instant game over, even after her party merges with Alm's.
Some leftover voice clips imply that Berkut was considered as a playable character.
Similarly, Fernand has some extra lines that imply he could've been a playable character, too. While it can partly be explained by him being available in the Rise of the Deliverance DLC, the biggest example of this is a mourning clip for Clive.
Celica has a set of voice clips for battle as a Witch, meaning there may have been plans for Gameplay and Story Integration in Alm's battle against her, instead of just being a Cutscene Boss.
God Never Said That: Faye's Base-Breaking Character status led some fans to spread rumors of developer interviews confessing that she was written to be intentionally unlikable, or that she was intentionally made that way to be a Deconstruction of the Unrequited Love character archetype (like Catria). Actual developer comments were nothing of the sort, simply stating that she was added to give more gender diversity to Alm's initial party and to add a potentially interesting subplot to the game.
The Wii virtual console port of Gaiden has been unavailable for purchase since the Wii Shop Channel's closure in January 2019. However, the Nintendo 3DS and Wii U eShops have shuttered on March 27th, 2023, meaning that the game, as well as its remake Echoes: Shadows of Valentia, have become increasingly rare. To make matters worse, Gaiden itself is one of the few Famicom games that haven't been ported onto the Nintendo Switch, even though the original Shadow Dragon and Mystery of the Emblem, as well as Genealogy of the Holy War, are included as part of the Nintendo Switch Online subscription service in Japan, and the formermost game had a worldwide limited release on the console as well.
All of Echoes: Shadows of Valentia's DLC packs, as well as the free Mila's Bounty DLC, are completely unobtainable without hacking.
Ten Gaiden characters appear in Fire Emblem: Awakening as SpotPass units: Alm, Clair, Clive, Celica, Boey, Valbar, Luthier, Deen, Nomah, and Mycen. Since Gaiden wasn't released outside of Japan before getting its remake, this was the first time many players heard of these characters.
Faye from Echoes: Shadows of Valentia debuts in Fire Emblem Heroes one week prior to the Japanese release of Echoes and a month prior to its international release. Curiously, she debuted as an Archer, a class she can't be in the game proper.
The fifth DLC pack will feature first in-game appearances of several Canon Foreigners from Fire Emblem Cipher - which is, notably, the first time Nintendo officially mentioned its existence outside Japan.
Gray's early line of "Shut up, Tobin" quickly became a meme due to its delivery. Max Mittelman, Gray's voice actor, has brought up the line at at least one con.
Chris Hackney, Boey's English VA, has acknowledged a number of Boey-related jokes on his Twitter. Most notable are the ones regarding his strange liking of flour and the infamous scream he makes in Act 4.
No Export for You: In Japan, Echoes had a really... bizarre collaboration with the convenience store chain 7-Eleven, where by using the in-store 7-Spot wi-fi and reaching Act 3 of the game, players could obtain the Seven Sword and Eleven Shield, alongside one of six exclusive provisions from a character known as the Flashy Man. While they still exist in the game's code, they were never distributed internationally through legitimate means, especially when the event was still running at the time.
Promoted Fanboy: Kenta Nakanishi was a fan of the original Fire Emblem Gaiden and had the honor of directing Echoes.
Remade for the Export: Gaiden was originally only released in Japan back in 1992, but the 2017 Nintendo 3DS remake (Shadows of Valentia) received an international release and, having come after Awakening and Fates, was probably produced in part with the idea that it was easier to export. They decided 'Echoes' was a good title to use to appeal to international players.
In the original game, many people claimed Saber and Genny got together because they were two of the only characters who had their endings saying they got married, but the person they married being not revealed. The main reason why many shipped it was because Genny's ending said she married an ally (or companion) and she didn't say who. Thus when Echoes came out and altered their endings a little, people began declaring that Genny and Saber was sunk, largely because of the age gap produced by Echoes' official ages. In reality, the two of them never were confirmed to be a pair (outside of perhaps the Gaiden novels), and are strongly hinted to not be married in the end, as Saber and Genny still marry the same unnamed character in both versions should the other be dead. Furthermore, Saber's ending mentions that he led a rather public life alongside his wife, which wouldn't work with Genny if nobody knew who she married like her ending states.
There was a small rumor that if Faye got an A support with Alm, Alm would get with her instead of Celica, even though this such a thing is not possible given the game's mechanics.
The various alcoholic drinks in Shadows of Valentia were originally supposed to act as health and fatigue recovery items instead of only being utilized as potential offerings to Mila's Servants. Their usability would have been restricted to characters that were 20 years of age or older. This is also why all the playable characters are given specific ages, though these are not visible normally and only exist as leftovers in the game's code.
Some characters (like Alm and Saber) have recorded mourning voice lines that were supposed to play after Celica's death in battle, indicating that at some point, she could be killed without causing a game over.
Berkut has a full set of quotes in Shadows of Valentia's files, indicating he was considered to become playable at one point in development. Fernand, while officially playable via DLC, also had a full set of quotes data mined before the DLC was released, indicating that he too was likely meant to be a fully playable character at some point in development.
According to a developer interview, Lukas was at one point planned to be much more of a Deadpan Snarker. As Fire Emblem Heroes was in development before Echoes was finished, Lukas' Japanese title (something along the lines of "Sharp-Tongued Cynic") in that game was based on this early personality.
Echoes was nearly released the same year as Fire Emblem Fates, at least in Japan. After Fates came out, IntSys debated releasing the game that year as they were unsure if the game would be a large enough draw for fans to get. Had they done so, the game's quality would've been notably less refined, as they were not quite finished by the year's end. However, the group decided to wait and polish the game a bit more, resulting in it being delayed to early-mid 2017, a move that they ended up realizing was the right call.
The developers considered adding modern Fire Emblem mechanics such as a customizable main character and Supports affecting relationships. They decided against this as such additions would complicate the plot more than necessary and it was better to keep it linear.
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