Franchouchou is coming back with a season 2 titled: Zombie Land Saga Revenge. The new Season is set to release in the 2021 spring anime season.
Here is the trailer that was released on Dec. 31, 2020.
They also released some awesome promo art too.
More information about the anime can be found at : https://myanimelist.net/anime/40174/Zombieland_Saga__Revenge