While the Switch’s emulator makes the game look significantly sharper, there are some scenes which don’t look exactly like they did before.
The most notable example of this is a scene featuring Skull Kid, where he’s surrounded by a colourful aura.
The Legend of Zelda: Majora's Mask - Switch Online trailer
While the aura is present in both versions of the game, it’s far more prominent in the upcoming one, which will be added to Switch Online on February 25.
This is presumably because the aura was made partially transparent on the N64, but the Switch emulator isn’t applying the transparency in the same way (if at all).
Another difference can be seen in the scene where the moon crashes to the ground, with the flame effect looking noticeably different in the Switch version.
The Switch’s N64 emulator has shown issues with transparency in the past. When the N64 library initially launched in October, players noted issues with The Legend of Zelda: Ocarina of Time, primarily its lack of water transparency and its inability to properly handle fog.
In November, Nintendo of America’s president even commented publicly on the issue and said the company was taking criticism of Switch Online’s N64 emulation “very seriously”.
An update last month, however, provided evidence that Nintendo was slowly improving its N64 emulation.