In Generation 9, the Poke Ball of the offspring is determined by:
- The female.
- The non-Ditto Pokemon when breeding with Ditto.
- Or, if you have two Pokemon of the same species, there's a 50/50 chance to inherit each ball.
This means that if you want a Meowscarada in a Nest Ball, you would have to have already obtained one. As you can only obtain Sprigatito in a Poke Ball at the start of the game, the only way to get a Nest Ball Meowscarada in Scarlet and Violet is to have caught it in a Nest Ball in a previous 7 Star raid, or by trading with someone who has any of the Sprigatito line in a Nest Ball. I'd recommend asking around in a larger community or looking on the Home GTS.
Hope I helped!