CoraxCorvus

Sure, a priority move means a change in plans, IF they lead with it. The reason to taunt is because you as you said sleep last for 1-3 turns, but only the first turn is guaranteed. If you switch on turn one of sleep, then evoboost on turn two, then baton on turn three, it could work, but... unlikely. Depends on how many resets you want to do. With taunt, you make sure they have to use an attacking move, thus knocking out purrloin so that eevee can switch in after the prankster yawn, protect during the drowsy turn, then evoboost the guaranteed sleep turn, and baton pass on the second sleep turn. Still runs the chance that they wake up after one round of sleep, but that is better odds at least. Of course you could always attempt something else with your yawn lead, if they survive the first round. Yawn, sub, sub, baton to another set-up sweeper like Vivillion who can sleep them again and quiver dance.

(My Prankster Yawner is actually a Meowstic in Rejuv at least, but that is neither here nor there) The idea is for the first pokemon to die to give a free switch in for eevee. Eevee with be in, use protect on the one turn you need to wait for yawn, then the opponent will be asleep. IF the opponent refuses to knock out your lead, then things get fun. First Purrloin prankster Substitute to survive the drowsy turn, followed by taunt on the guaranteed sleep turn. If the sub was broken, reapply it to survive the wake up round, then once it wakes up, prankster yawn and get killed so Eevee can be brought in.

Eevee can learn protect, right? So would you just Prankster Yawn on a suicide lead, (or maybe an eject button, never once actually used one), send in Eevee and use protect until the drowsy pokemon sleeps. Then you have a free turn to Extreme Evoboost and Baton Pass on the second sleeping turn. The worst that could happen* is the AI consistently switching the drowsy pokemon, then yeah, you would need the Focus sash. *Or a Dark type lead or a pokemon with Feint.

Alternatively, you can do it manually. I just search (hit the windows key and type) game.rxdata to find the reborn save folder and then it is just a matter of organizing your playthroughs into folders. Not sure if there is any benefit to it in this case, but it is useful if you play any other fan games that don't have multiple save slots.

It's been a while, but I think the first is chikorita, in the building where you rescue Cain after returning to Kiki.