Managing threat lists... Manually creating STIX and IOC files?

So my department manages OT and ICS critical infrastructure in an air gapped (offline) network.

I'm getting crosstrained by our areas cybersecurity lead on adding threat intelligence to our IDS and SIEM. He takes these emails from our corporate security guys with IPs, domains, or hashes to block...and basically manually creates these as XML-like STIX and IOC files so the threat intel can be imported into our security tools.

It takes him like, two hours to create these threat intel …

cybersecurity files ioc lists threat