Along with the other two alt characters based on them (the zombie and enderman), plus stages, spirits and other content based on the Minecraft franchise. Here’s the official announcement by Nintendo of America:
— Nintendo of America (@NintendoAmerica) October 14, 2020
So yeah, if you own the Second Fighter Pass and are interested in trying out these Minecraft characters in Super Smash Bros Ultimate, now’s your chance. Update the game, and get playing!