The Japanese say it Po-keh-mon, because ケ carries a different vowel sound to our ké.
Re: Cinccino - I see it and Italian arias sing to me. It's indeed (S)in-Chi-No[h]. Italian 'ch' (derived from cc and c) doesn't have a hard ch(uh) sound like English unless it is before an i or an e, which is why Cinccino carries the same ch sound as cappuccino. Otherwise, cc usually has a soft k sound.