Most of them do, yeah. You may hear a bit of a “tongue click” or something with others first before the “s”. A lot of first-language English speakers seem to really struggle when they see two consonants together that they haven’t previously encountered.

I read it as choonami which is still not very helpful

It should be a "hard ts" which is something we mostly picked up from the French that is also a sound used in Japanese. So there should be a difference between saying "tsu" and saying "sue."

Tsu should be pronounced with teeth together and pushing air out through the teeth first, tongue against the lower front teeth for the hissy-t sound, before the vowel. (it's hard to write how to pronounce a word)