You could just tell your lower opers about $<servermask> for a /notice target, eg most IRCd's support /notice $*.com <message> to send <message> to all servers with a server name ending in .com (most IRCd's restrict said server name masks to requiring at least the TLD, some like UnrealIRCd do allow $* though)
Of course that option is only available to /oper'ed users anyway, and there's little Anope can do to STOP an oper using that method as Anope can only react to it at most.