[NiLuJe]

As there's no formal or even slightly coherent standard for CBZ metadata, no.

I just push 'em with a sane filename, which is good enough for the FM, and match 'em manually to the source ePub in my Calibre library, which makes it good enough for the Calibre metadata search. (I think? I have so few of 'em I don't really need to search for them ^^).

(e.g., as far as the actual file is concerned, the process is usually Kobo/HumbleBundle; take whatever most appropriate source there is and "sanitize" it as necessary, explode it, run images through ImageMagick to generate perfectly screen-sized and dithered PNGs, bundle in an uncompressed CBZ).