The Unicode Standard and ISO

Hello,

There are several mentions of synchronization with related standards in
unicode.org, e.g. in https://www.unicode.org/versions/index.html, and
https://www.unicode.org/faq/unicode_iso.html. However, all such mentions
never mention anything other than ISO 10646.

I was wondering which ISO standards other than ISO 10646 specify the
same things as the Unicode Standard, and of those, which ones are
actively kept in sync. This would be of importance for standardization
of Unicode facilities in the C++ language (ISO 14882), as reference to
ISO standards is generally preferred in ISO standards.

-- 
Martinho