With CIS on, Batman loses. He do half the over the top, potentially lethal scenario's posters come up with, since he doesn't kill (And plunking Supes in the middle of a Green K cave would kill him.)
Without the help of his parents....
Superman amps.
Then flies off faster than the speed of light. Uses his supervision to observe what Batman did in his year of prep (all he needs to do is fly more than one light year away).
Then flies back, and all of Batman's plans are for naught.
I mean Superman could loot all the bombs on earth place then all the places Batman might go and wait to see if that works. He could gather bunker busters and toss them at mach speed over and over again until he got Batman in his cave alot of ways for Supes to win.
Batman still wins.. he knows Clark's weaknesses so he'll use those to his advantage.. he could certainly build a kryptonite batsuit filled with krypto bat a rangs and gases, etc and Supes dies
lols .. I have never ever cared about PIS neither here nor in the MVF.. Batman is given a year prep, in that time he will build what is necessary to defeat Clark
PIS is what enables Batman to do a great deal of the things he has. Not sure how that can be disputed or ignored.
If Superman sundips for a month, he'll be so astronomically powerful and fast that nothing Batman can feasibly do will matter in the end. Batman's a decent prep artist, but he's not a super genius in the vein of Richards or Doom, and his tech isn't close to being on the same level, either.
Realistically I don't see any scenario where Superman is beating Luthor who has access to all his resources for a year to take down superman without there being CIS and PIS in favor of superman
So consequently putting Batman in place of Luthor isn't changing much if anything at all.