Nintendo has stated that Metroid Prime 4 and Bayonetta 3 will both launch in 2018, despite neither game having yet received a full trailer.
The curious claim was made in a post on Nintendo's official Norwegian site, which ran down the companies successes in 2017. However, the post then ends with the following statement:
"The year 2017 has definitely been Nintendo's year and we are looking forward to 2018, which will include new games like Bayonetta 3, Metroid Prime 4 and Kirby: Star Allies as well as many other games that we will reveal during the year.
Metroid Prime 4 and Bayonetta 3 have thus far only received two teaser trailers, with the former revealed at E3 2017 while the latter was debuted during The Game Awards 2017. As such, it doesn't seem likely that they'll be finished anytime soon, but Nintendo Norway appears to think differently.
If this wasn't a quote from an official Nintendo source then it would be easy to dismiss it. We know nothing about Metroid Prime 4 other than it's currently in development, while Bayonetta 3 was only recently announced. Perhaps this is the case of someone in Nintendo getting their wires crossed, or it could mean that Nintendo has one very exciting (and unexpected) 2018 planned. We'll have to wait and see.
(H/T Twitter / Wario64)