Quoting any child meta site's
Reputation on this per-site meta is derived entirely from the main site; nothing to show.
Which is consistent with what's shown as part of the user info: main site reputation.
/users does not have a reputation page, it instead displays activity which counts upvotes and accepts:
On a user's profile, there is no reputation tab (first screenshot), as on the main site (second screenshot, fourth from the right).
On the other hand, reputation badges exist and are attainable:
That last badge has been awarded five times so far on Meta.SU, most recently in August
The badges on "reputation-less" child meta sites make no sense at all from a user's POV. While there are badges, and they can be awarded, there is neither a reputation tab in the user profile, nor a
/reputation history. I don't believe for one second that this, as a whole, was deliberately designed this way, and if it was, it should be changed.
This should be fixed e.g. by completely deleting the relevant badges from the child meta sites.