The entirety of the Mega Man Zero series and the Mega Man ZX series will be released together in the Mega Man Zero/ZX Legacy Collection. This information comes from a supposed leak from the PlayStation store.
From the game’s PlayStation store page:
Mega Man Zero/ZX Legacy Collection brings together six classic titles in one game: Mega Man Zero 1, 2, 3, and 4, as well as Mega Man ZX and ZX Advent.
In addition to the original games, this package includes an artwork gallery, music player, special filters, and much more. Casual Scenario Mode and a Save-Assist feature are available for those who would like to enjoy the story at their own pace. Players can also try their hand at the new leaderboard-based Z Chaser Mode, an exclusive new mode created just for this set of games.
The trailer above currently lists PlayStation 4 as the only platform, but this could be because it was taken from the PlayStation store. Other consoles should be announced in the future. According to the trailer, Mega Man Zero/ZX Legacy Collection will be released on January 21, 2020.