You can download Wildstacker for free : https://www.spigotmc.org/resources/%E2%9A%A1%EF%B8%8F-wildstacker-%E2%9A%A1%EF%B8%8F-spawners-entities-drops-blocks-%E2%9A%A1%EF%B8%8F-1-17-support.87404/
BeastSpawners
https://www.spigotmc.org/resources/beastspawners.40051/
$6.00
It's a nice way how to make griding more interesting into your SkyBlock | Factions | Survival Server.
Also, if there's a similar plugin that supports 1.17 please DM me <3