On the EU IPO (European Union Intellectual Property Office) website, new listings have appeared for various Nintendo controllers. This includes those for the NES, SNES, Nintendo Switch and most importantly Nintendo 64. Considering the timing of the listing, it could be that Nintendo is gearing up for Nintendo 64 Mini.
The NES and SNES logos are the ones that you can find the mini console boxes. Naturally, this still could be anything, but it seems unlikely given the registered goods and services tag. Either way, the whole situation will add some fuel to the fire! Thanks to nicodarunia for the heads up!