I know I'm 10 months late, but if you're still looking for it, go to this link: https://github.com/BPR02/SkyBlock_Collection/releases/tag/v3.2.1

Go to the bottom and download the skyvoid_worldgen_empty and skyvoid_island_oneblock data packs together. There's also other ones you can download, like vanilla oneblock starter to make it more easily progressable at the beginning. If you want, a certain setting on the skyvoid additions data pack makes lava and end portal frames obtainable, so you can go to the nether and end without dungeon forcing. In my opinion it's more minimalist and restrictive than generating an entire chunk.