I mean thats a good plan or at least a start, and I can see why the other are undesirable, but not my point. let me reword:
why does the phrase "This is not the True Rinnegan" need to be said?
why do we have to bring this sentence up and make it apart of the canon this roleplay?
because in most cases, the phrase doesn't mean anything. the flashier stuff can simply be a myth. the sealing of the ten tails can simply be that and the moon need not be its leftover body. for all anyone knows, the rinnegan they obtain IS the real one and whatever powers it has, is the power it always did have and the stuff that it doesn't, are probably just a myth someone made up. the only way I can think of anyone knowing its NOT the real rinnegan is if someone like Zetsu or Hagoromo's ghost outright tells them, and those are old rare beings that no one knows exists. so whats so important about making it important to state there is another kind of rinnegan out there at all? what purpose does complicating this serve?
because all it will do, is convince Kimiko that there is yet more she needs to obtain. that the rinnegan she currently has is just a stepping stone to another. to be fair, her quest for all jutsu probably won't be ended by the end of the roleplay either, but still why does this need to be a thing? I need a reason beyond "well its canon". because this is one of the things that if included at all even slightly, could derail things or overcomplicate something that didn't need to be. we could just y'know, have the rinnegan. and that this rinnegan is just nerfed in this canon because we're a different canon. nothing more needs to be done, and its simpler and less problematic. including the phrase "This is not the True Rinnegan." is a complication.
how does this complication provide benefit?