We've been eagerly awaiting any update on the status of Joker's inclusion in the Super Smash Bros. Ultimate roster since he was announced last December. In today's Nintendo Direct, it was revealed that Joker will be joining the already humongous roster by the end of April. Joker is available individually as part of the Challenger Pack 1 or as part of the Fighters Pass, which unlocks the next five downloadable fighters.
In addition, Nintendo also announced the version 3.0 update for Ultimate, though no further details were given on what this entails.
Source: Nintendo Direct