This appears to be a , not an official retail version. If you found it online, it’s likely an unauthorized custom edition containing fan-added songs (since official Just Dance 4 DLC updates stopped long before 2021).
from that version you're most excited to dance to? just dance 4 special edition paldwiiwbfs 2021
While was the latest release around the time this file surfaced, it was the first main-series game not released for the original Wii, making older titles like Just Dance 4 highly sought after for those still using the legacy console. Just Dance 4 [Special Edition] PAL Wii - PriceCharting This appears to be a , not an official retail version