Nintendo have just announced, via the recent Nintendo Direct Presentation, that Metroid Zero Mission will be coming to the Nintendo Switch Online app later today.
We will update this article if there are any more updates regarding its release.
UPDATE – Metroid Zero Mission is now available to Nintendo Switch Online Expansion Pass users. To access the game, subscribers will need to download the latest version of the Game Boy Advance Nintendo Switch Online application (1.8.0).
In addition, the NSO version of Zero Mission comes with the Metroid Fusion Gallery pre-unlocked, which was previously only accessible using the GameBoy Advance’s Link Cable feature.