Nintendo a month or so back at GDC 2017 revealed that during the development of Breath of the Wild, the team created a 2D prototype in the image of the original Zelda game to test gameplay ideas and philosophies.
I suggested at the time that Nintendo should consider releasing a Maker-style game based on the original Zelda assets. Rather than wait around for that day to (probably never) happen, one person decided to make it a reality on their own accord.
Designer Winter Drake has released Zelda: Breath of the NES over on itch.io which is more or less a NES port of the latest Zelda game. Free for Windows PC and built in Game Maker Studio, the game features day and night cycles, interactive environments, impressive physics and excellent lighting effects.
In an interview with Kotaku, Winter Drake said the project is still in its early stages and there is a lot more to come including more areas with distinct elements and atmospheres, puzzle elements for dungeons and lots of ways to creatively kill enemies.
Winter Drake even has a plan in place should Nintendo come knocking with the inevitable cease and desist letter. When that happens (it will happen), Winter Drake aims to continue development using original characters.
I suppose that's worth a try although given how much the game looks like Zelda, I'd be surprised if a character change alone is enough to send Nintendo away peacefully.