出しゅっ身しん者しゃ

〈場ば所しょ〉出しゅっ身しん者しゃpeople who come from 〈場所〉
このチームには関かん西さい出しゅっ身しん者しゃが多おおい。
There are many people from the Kansai region on this team.
〈場ば所しょ〉の出しゅっ身しん者しゃan alumnus/graduate of 〈場所〉
彼かれはハーバード大だい学がくの出しゅっ身しん者しゃだ。
He is a graduate of Harvard University.
〈組そ織しき〉出しゅっ身しん者しゃa former member of 〈組織〉
彼かれは大おお手て企き業ぎょう出しゅっ身しん者しゃで、今いまは独どく立りつしている。
He's a former employee of a major company, and now he's independent.
出しゅっ身しん者しゃが多おおいthere are many people from (a certain place/school/group)
この学がく部ぶは地ち方ほう出しゅっ身しん者しゃが多おおい。
Many students in this department are from rural areas.

Kanji

卒そつ業ぎょう生せい sense 1
卒業生 refers specifically to someone who completed a course of study, while 出身者 more broadly covers anyone who attended, including those who didn't finish.
同どう窓そう生せい sense 1
同窓生 emphasizes shared alma mater and fellow classmates, while 出身者 simply identifies the person as having come from that school.

在ざい校こう生せい sense 1
在校生 means a currently enrolled student, the opposite of 出身者 who has already left the school.

出しゅっ身しんN3
出身 is the abstract fact of where someone is from or studied, while 出身者 is the actual person who is from that place or institution.

Compound of 出身 (origin, alma mater) + 者 (person). The meaning follows directly from the components.