these potions were brewable in the very first pre-release that introduced potions. But that was back when potions were brewed in the cauldron instead of a brewing stand.
Anyway the recipes are:
Nausea Splash Potion: Nether Wart -> Brown Mushroom -> Gunpowder
Blindness Splash Potion: Nether Wart -> Ink Sac -> Gunpowder
Those potions require atleast 500MCMMO levels to be able to brew them.
Goodluck x ugur