Mini-consoles are hot-ticket items this year, as people get nostalgic seeing the consoles of their childhoods sitting beneath their TV with preloaded games. Sony announced their own just the other day, while the NES Classic and SNES Classic have both been selling well for Nintendo even this year. It makes sense, then, that Nintendo would keep the train rolling with a Nintendo 64 Classic before long and a new trademark in Europe indicates it might be sooner rather than later.
Caught by Business Insider, Nintendo has trademarked a silhouetted image of the Nintendo 64 controller, identical in theming to the NES and SNES controllers on their respect controller boxes. While this isn't a slam dunk that a N64 Classic is coming, as Nintendo has also trademarked a similar image for the Switch, it is a pretty good sign that something is on the way.
A N64 Classic would, presumably, come preloaded with around 20 games. What games do you think need to be in to represent the N64 library? It is possible that licensing might prevent games like Goldeneye from getting added, or issues with Rare stopping their games from appearing, but it's all guesswork right now.
Previous classic consoles had been announced in the summer with a September release, for which the timeline has now shifted greatly. If a N64 Classic does get announced for this year, a Winter release window pitting it directly against the PlayStation Classic is not out of the question.