Gaming Replay a Portuguese store has put up listings for Mass Effect Trilogy for the Nintendo Switch, Xbox One, and PS4 versions. This was only for a brief time on September 16, 2020, before they were pulled down.
All three of the releases had preliminary box art, even though the PEGI was inaccurate on them. In Europe only Mass Effect: Andromeda had a PEGI 16 rating, which all three of the tentative listings had. Mass Effect 1, 2, and 3 were all PEGI 18 rated. The price was the same for the PS4 and Xbox One versions and was around €59.99, while the Nintendo Switch was cheaper at around €49.99. And also the listings claimed they were to be released by October of 2020.
All of this also does seem to come together with other information such as Jeff Grubb suggested in GamesBeat Decides episode 161 that a Mass Effect Trilogy collection was in development, and also in the podcast, he suggested it would be announced and released in October 2020. And more recently, a Nintendo Direct Mini: Partner Showcase was announced for September 17, 2020, and Grubb tweeted, “I’ve hinted at one of the things that will be in it.”