Acrobat is limited to basic pagination.
Quite Imposing would be a good tool for this; I am not familiar with PDFSnake.
Quite Imposing performed both of these tasks in about 2 seconds.
FWIW the usage of folded signatures is common in Perfect Binding, but not necessary. You could simply impose as "Cut Stacks" via Step & Repeat.
Quite Imposing's Perfect Bound
