MoinMoin is both a wiki engine and a wiki markup format.
Zwiki supports MoinMoin markup as one of its page editing formats. Not every aspect of that format works really (in theory things should be documented in MoinMoinMarkup), but when you're used to MoinMoin markup, this might just be the thing for you.
Some old discussions:
I've started to use MoinMoin in our company last year, because I wasn't aware of ZWiki at this time. Has anybody already tried to move some hundred pages from a former MoinMoin Wiki into ZWiki? -- Peter Funk
Hi, Peter. I've moved only a few dozen. Because StructuredTextSucks (IMO), I'm writing a MoinMoinMarkup scheme to ease my "transition." I would love to get feedback about it, and eventually see it go into the main ZWiki tree. -- Chad Miller
Zwiki supports MoinMoin markup as a format - no need to do anything to move the pages? - Mike