See https://man.freebsd.org/cgi/man.cgi?query=zfsprops&sektion=7&manpath=freebsd-release Manpage zfsprops(7) refers to a non existent command/manpage exportfs(8). Checked on 13-STABLE, CURRENT and 13.2-RELENG.
Just a note: there are other linux-specific settings/references in openzfs man pages, so we need a way to have freebsd specific ones, but without just simply duplicating and fixing those.