There have been rumors circulating about the upcoming 35th-anniversary celebrations for the Super Mario Bros. series. According to a number of different outlets, Nintendo is planning on bringing all of the major 3D Mario games to the Switch this year, including ports of Super Mario 64, Super Mario Galaxy 1 & 2, and Super Mario Sunshine.
2021 will mark the 35th anniversary of The Legend of Zelda series and it's possible that Nintendo could be planning a similar event for that franchise. The Switch currently has access to Breath of the Wild, A Link to the Past, the remake of Link's Awakening, Zelda II: The Adventure of Link, and the original game in the series. It would be easy enough to port the remaining 2D Zelda games to the system (with the possible exception of the DS/3DS titles), but what about the 3D Zelda games?
There are a couple of notable omissions from The Legend of Zelda series on the Switch. Still, a few persistent rumors from a couple of years ago suggested that more games are on the way; it's possible that we could see an influx of 3D Zelda titles next year, based on a few different factors.
The Conspicuous Absence Of Twilight Princess HD/Wind Waker HD On The Switch
The age of the Wii U is well and truly over, as Nintendo and several third-party developers have had no problem porting all of its best games to the Switch. Games like Bayonetta 2, Tokyo Mirage Sessions, Donkey Kong Country: Tropical Freeze, Hyrule Warriors, New Super Mario Bros. U, and Pokkén Tournament have all made their way to the system over the past three years in improved forms.
The two games from the Wii U era that are conspicuous by their absence on the Switch are The Legend of Zelda: Twilight Princess HD and The Legend of Zelda: Wind Waker HD. These two games seem like they would be easy to port to the system, as they never relied heavily on GamePad support. These two games are highly requested and they're sure to do well when not shackled to the Wii U, but they have yet to be ported to the Switch and no one is sure why.
The Skyward Sword Statement
In November 2018, Eiji Aonuma made comments at a Zelda concert which suggested that The Legend of Zelda: Skyward Sword is coming to the Switch. It only took Nintendo two days to refute those claims, but it still caused a ton of speculation regarding the game. The fact that Nintendo went out of its way to refute the claim is considered to be suspicious by some, as the company has had no problem letting a false story brew for weeks for free publicity (as was the case with the rumored The Legend of Zelda Netflix series) before releasing a statement.
The Legend of Zelda: Skyward Sword would require a lot more work than the HD games on the Wii U to bring to the Switch. The game would need to be reworked with HD visuals, while the control scheme would need to be adapted for the Joy-Cons. Then again, if the game has been in development for at least two years (and has another to go), then that's plenty of time to work out the kinks and bring it to the Switch.
Bringing Back The 64 Era
This leaves two of the most beloved games in the series - The Legend of Zelda: Ocarina of Time and The Legend of Zelda: Majora's Mask. HD remakes of these games are some of the most highly-requested Nintendo titles and releasing them is a license to print money. The rumors regarding the Super Mario Bros. anniversary have stated that Super Mario 64 is being ported or updated for the Switch, and the two N64 Zelda games have a leg up, thanks to the 3DS versions of the games. The Legend of Zelda: Ocarina of Time and The Legend of Zelda: Majora's Mask both received updated ports for the 3DS that added QoL improvements, so these could form the basis for HD versions of the game.
The Legend of Zelda series contains some of the greatest video games ever made and there are fans who still keep hold of their old Nintendo consoles in order to play them. There have been all kinds of rumors regarding the 35th-anniversary of the Super Mario Bros. series and a port of Metroid Prime Trilogy coming to the Switch in the future. If those turn out to be true, then a return to the Hyrule of old can't be too far behind.